@article {4335, title = {Halogen-related photodissociation in atmosphere: characterisation of atomic halogen, molecular halogen, and hydrogen halide}, year = {2021}, abstract = {

Atomic halogen elimination from halogen-related compounds plays a vital role in the depletion of the ozone layer and is well investigated. However, the probabilities for elimination of molecular halogens and hydrogen halides are rarely scrutinised. We develop distinct method for the investigation of each kind of fragment. Velocity-mapping ion-imaging was employed to study the atomic halogen elimination from alkyl halides and aryl halides, focusing on the fractions of the translational energy release, the quantum yields of the atomic fragments, transition probability for curve crossing, competitive halogen-related bond fission, and anisotropy parameters to understand their dynamical complexity. Cavity ring-down absorption spectroscopy was implemented to investigate the molecular halogen fragments dissociated from the aliphatic halides and acyl halides for their optical spectra, vibrational branches, quantum yields, and the dissociation mechanisms. Time-resolved Fourier transform infrared emission spectroscopy was employed to confine the primary products of hydrogen halide elimination from acyl halides in the presence of Ar gas. It is, for the first time, to overview these existing small halogen-related fragments eliminated from halogen-containing compounds. The detailed characterisation of these fragments should unveil complicated halogen-related dissociation mechanisms which may supplement the current knowledge and help with the photochemical assessment of halogen-related environmental issue. {\textcopyright} 2020 Informa UK Limited, trading as Taylor \& Francis Group.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85092305204\&origin=inward\&txGid=4ad722d1e18aab24e1f16fe03e7c2e85}, author = {Lin, K.-C., Muthiah, B., Chang, H.-P., Kasai, T., Chang, Y.-P.} } @article {4337, title = {Carbon dot nanoparticles exert inhibitory effects on human platelets and reduce mortality in mice with acute pulmonary thromboembolism}, year = {2020}, abstract = {

The inhibition of platelet activation is considered a potential therapeutic strategy for the treatment of arterial thrombotic diseases; therefore, maintaining platelets in their inactive state has garnered much attention. In recent years, nanoparticles have emerged as important players in modern medicine, but potential interactions between them and platelets remain to be extensively investigated. Herein, we synthesized a new type of carbon dot (CDOT) nanoparticle and investigated its potential as a new antiplatelet agent. This nanoparticle exerted a potent inhibitory effect in collagen-stimulated human platelet aggregation. Further, it did not induce cytotoxic effects, as evidenced in a lactate dehydrogenase assay, and inhibited collagen-activated protein kinase C (PKC) activation and Akt (protein kinase B), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) phosphorylation. The bleeding time, a major side-effect of using antiplatelet agents, was unaffected in CDOT-treated mice. Moreover, our CDOT could reduce mortality in mice with ADP-induced acute pulmonary thromboembolism. Overall, CDOT is effective against platelet activation in vitro via reduction of the phospholipase C/PKC cascade, consequently suppressing the activation of MAPK. Accordingly, this study affords the validation that CDOT has the potential to serve as a therapeutic agent for the treatment of arterial thromboembolic disorders. {\textcopyright} 2020 by the authors.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85087121148\&origin=inward\&txGid=6cce48f541f4433422a935514072f626}, author = {Lee, T.-Y., Jayakumar, T., Thanasekaran, P., Lin, K.-C., Chen, H.-M., Veerakumar, P., Sheu, J.-R.} } @inbook {4333, title = {Computational and experimental analysis of carbon functional nanomaterials}, year = {2020}, abstract = {

Density functional theory (DFT) as one of molecular simulation techniques has been widely used to become rapidly a powerful tool for research and technology development for the past three decades. In particular, the DFT-based theoretical and fundamental knowledge have shed light on our understanding of the fundamental surface science, catalysis, sensors, materials science, and biology. Oxygen, nitrogen, boron, phosphorus, and sulfur are the most common heteroatoms introduced on the functional carbon nanomaterials surface with different surface functionalities. This book chapter aims to provide a pedagogical narrative of the DFT and relevant computational methods applied for surface chemistry, homogeneous/heterogeneous catalysis, and the fluorescence-based sensing properties of carbon nanomaterials. We overview several representative case studies associated with energy and chemicals production and discuss relevant principles of computationally driven carbon nanomaterials design.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85089333063\&origin=inward\&txGid=885c8f4ced0274402e107dbf56896167}, author = {Veerakumar, P., Dhenadhayalan, N., Lin, K.-C.} } @article {4343, title = {Fabrication of Platinum-Rhenium Nanoparticle-Decorated Porous Carbons: Voltammetric Sensing of Furazolidone}, year = {2020}, abstract = {

This study discusses the prospect of using biomass waste material, such as Cassia fistula (golden shower) fruit, as a carbon precursor in the development of new carbon material for the sustainable electrochemical sensor application. We successfully synthesized platinum-rhenium nanoparticles decorated on a porous activated carbon (Pt-Re NP/PAC) nanocomposite through the incorporation of metal precursors such as platinum(II) acetylacetonate (Pt(acac)2) and dirhenium decacarbonyl (Re2(CO)10) via a facile thermal reduction process. A variety of physicochemical and electrochemical methods were employed to characterize the morphology, structural, and electrochemical properties of the Pt-Re NP/PAC material. We then looked into the analytical behavior and applications of GCE modified with Pt-Re NP/PAC (Pt-Re NP/PAC/GCE) for the determination of furazolidone (chemotherapy drug) by employing different voltammetric techniques. The influence of experimental conditions such as scan rate, pH, accumulation time, amount of the modifier, and sample concentration on the peak current of the furazolidone was studied. The proposed drug sensor exhibited a wide linear range (WLR) for furazolidone in 0.05 M phosphate-buffered saline (PBS, pH 7.0) from 1.0 to 299 μM with a limit of detection (LOD) of 75.5 nM and appreciable sensitivity (5.52 μA μM-1 cm-2) which were calculated from linear sweep voltammetry (LSV). In addition, these analytical parameters including WLR, sensitivity, and LOD were estimated to be 0.2-117.7 μM, 19.20 μA μM-1 cm-2, and 20.8 nM and were obtained using differential pulse voltammetry (DPV). Therefore, the prepared Pt-Re NP/PAC modified sensor could be a potential candidate for the determination of furazolidone in pharmaceutical formulation, human urine, and blood serum samples, and the results are appreciable. Copyright {\textcopyright} 2020 American Chemical Society.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85081718605\&origin=inward\&txGid=0e3997668cd554c0d50dbd4593486633}, author = {Veerakumar, P., Sangili, A., Chen, S.-M., Pandikumar, A., Lin, K.-C} } @article {4332, title = {Non-invasive and time-dependent blood-sugar monitoring via breath-derived CO2 correlation using gas chromatograph with a milli-whistle gas analyze}, year = {2020}, abstract = {

A clear and positive correlation between the CO2 concentration and the blood-sugar level has been observed via a noninvasive and time-dependent monitoring of CO2 concentration from human breath, which is carried out by using a homemade gas chromatography (GC)/milli-whistle compact analyzer. The time-dependent sampling of the CO2 concentration correlated between 5.0 to 5.6\% (1\% = 104 ppm) in accordance with blood-sugar level variations of 80 to 110 mg/dL. The analytical method results in a rapid, continuous and non-invasive determination of blood-sugar level via measurement of the CO2 concentration exhaled from the lungs.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85086346692\&origin=inward\&txGid=18343f6799af3a6c2327840cdd168878}, author = {Lin, C.-H., Wu, L.-X., Chen, K.-H., Lo, H.-F., Lin, K.-C., Kasai, T., Chen, C.-C., Shih, C.-H., Manzano, M.C., Santos, G.N., Man} } @article {4341, title = {An overview of palladium supported on carbon-based materials: Synthesis, characterization, and its catalytic activity for reduction of hexavalent chromium}, year = {2020}, abstract = {

Palladium plays a pivotal role in most of the industrial heterogeneous catalysts, because of its unique properties such as well-defined structure, great intrinsic carrier, outstanding electronic, mechanical and thermal stability. The combination of palladium and various porous carbons (PCs) can widen the use of heterogeneous catalysts. This review highlights the advantages and limitations of carbon supported palladium-based heterogeneous catalyst in reduction of toxic hexavalent chromium (Cr(VI)). In addition, we address recent progress on synthesis routes for mono and bimetallic palladium nanoparticles supported by various carbon composites including graphene-based materials, carbon nanotubes, mesoporous carbons, and activated carbons. The related reaction mechanisms for the Cr(VI) reduction are also suggested. Finally, the challenge and perspective are proposed. {\textcopyright} 2020

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85083042829\&origin=inward\&txGid=75333d7a7524b9a78410259acaf60de2}, author = {Veerakumar, P., Lin, K.-C.} } @article {4342, title = {Paper flower-derived porous carbons with high-capacitance by chemical and physical activation for sustainable applications}, year = {2020}, abstract = {

Porous carbon nanosheets were prepared by the carbonization of paper flower via chemical and physical activation. The structural properties of the as-prepared carbons were characterized using the techniques, such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Raman spectroscopy, N2 sorption isotherms and X-ray photoelectron spectroscopy (XPS), while the related morphological analyses were conducted using scanning/transmission electron microscopy (SEM/TEM). The obtained carbons exhibit a high specific surface area up to 1801 m2 g-1 with a robust porous graphitic carbon layer structure, which provides the merits for potential application in energy storage and dye removal. We carried out potentiostatic and galvanostatic measurements using a three-electrode cell in 1.0 M H2SO4 aqueous electrolyte and achieved a specific capacitance of 118, 109.5, 101.7, 93.6, and 91.2 F g-1 at 1, 2, 4, 8 and 12 A g-1, respectively. The stability at 12 A g-1 was tested to reach 10,000 cycles with capacity retention of around 97.4\%. We have demonstrated that the paper flower-derived carbons at activation temperature 800 {\textdegree}C (PFC-800) can be used as a promising electrode material in supercapacitor. PFC-800 can also serve as an efficient sunset yellow dye removal, showing the maximum adsorption capacity for sunset yellow (Q0, 273.6 mg g-1). {\textcopyright} 2018 King Saud University

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85052750563\&origin=inward\&txGid=32b1ce80498eda2c369cf0dedebfab1a}, author = {Veerakumar, P., Maiyalagan, T., Raj, B.G.S., Guruprasad, K., Jiang, Z., Lin, K.-C.} } @article {4346, title = {Photochemically Synthesized Ruthenium Nanoparticle-Decorated Carbon-Dot Nanochains: An Efficient Catalyst for Synergistic Redox Reactions}, year = {2020}, abstract = {

Ruthenium nanoparticle (NP)-decorated carbon dots (Ru/C-dots) were fabricated as a potential catalyst in the application of both oxidation and reduction. The photochemical method was used to synthesize Ru/C-dot nanohybrids. The as-prepared Ru/C-dots exhibited a core-shell-based nanochain structure, in which the spherical nature of C-dots further evolved to a layer structure to homogeneously encapsulate Ru NPs. Such Ru/C-dots have excellent catalytic properties, which were demonstrated in the oxidation of flavonoids and concomitantly reduction of inorganic complex and organic dyes, each yielding a high catalytic rate constant. We also proposed an appropriate catalytic mechanism for each reaction. Higher catalytic activity was achieved by the synergistic effect of the encapsulated Ru NPs and the C-dots layer. Further, this nanohybrid was successfully applied to inspect a real aqueous sample. We anticipated that Ru/C-dots nanohybrid may open up a broad platform for the design of efficient multifunctional catalysts. Copyright {\textcopyright} 2020 American Chemical Society.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85082386439\&origin=inward\&txGid=b615afd55090f4f66e4e7b7bde024af4}, author = {Dhenadhayalan, N., Lin, K.-C.} } @article {4334, title = {Recent Advances in Functionalized Carbon Dots toward the Design of Efficient Materials for Sensing and Catalysis Applications}, year = {2020}, abstract = {

Since the past decade, enormous research efforts have been devoted to the detection/degradation and quantification of environmental toxic pollutants and biologically important molecules due to their ubiquitous necessity in the fields of environmental protection and human health. These fields of sensor and catalysis are advanced to a new era after emerging of nanomaterials, especially, carbon nanomaterials including graphene, carbon nanotube, carbon dots (C-dots), etc. Among them, the C-dots in the carbon family are rapidly boosted in the aspect of synthesis and application due to their superior properties of chemical and photostability, highly fluorescent with tunable, non/low-toxicity, and biocompatibility. The C-dot-based functional materials have shown great potential in sensor and catalysis fields for the detection/degradation of environmental pollutants. The major advantage of C-dots is that they can be easily prepared from numerous biomass/waste materials which are inexpensive and environment-friendly and are suitable for a developing trend of sustainable materials. This review is devoted to the recent development (since 2017) in the synthesis of biomass- and chemical-derived C-dots as well as diverse functionalization of C-dots. Their capability as a sensor and catalyst and respective mechanism are summarized. The future perspectives of C-dots are also discussed.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85075709311\&origin=inward\&txGid=ccd2f6212cdbc133b05693ae8a90f773}, author = {Dhenadhayalan, N., Lin, K.-C., Saleh, T.A.} } @article {4344, title = {Research Progress on Porous Carbon Supported Metal/Metal Oxide Nanomaterials for Supercapacitor Electrode Applications}, year = {2020}, abstract = {

Recently, transition metal/metal oxides (TMMOs) decorated on porous carbons (PCs) have been intensively focused on designing rational electrode materials for the promising future specific category of electrochemical energy storage and conversion technologies. In particular, TMMO incorporation with PC structures has become very attractive in the area of supercapacitors (SCs) mainly caused by their large accessible surface areas (SSA), together with the suitable pore size distributions (PSD), high electrical conductivity, and rapid redox reactions reversibly on the surface. The transportation of ions, as well as electrons in the bulk of electrodes, is fast as a result of optimal contact between electrodes and electrolytes at the electrode-electrolyte interface, thereby generating high specific capacities (Csp) of these PCs with TMMOs. We report a survey regarding recent advances in the fabrication and synthesis of TMMOs decorated on PCs with some physical characteristics and their applications for electrochemical capacitors. Some future trends and prospects for further development of the subject nanocomposites in application to next-generation supercapacitors are discussed. {\textcopyright} 2020 American Chemical Society.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85084048139\&origin=inward\&txGid=e640a2f45b72b84e9f1005257a7cf2cc}, author = {Veerakumar, P., Sangili, A., Manavalan, S., Thanasekaran, P., Lin, K.-C.} } @article {4340, title = {Roaming Dynamics and Conformational Memory in Photolysis of Formic Acid at 193 nm Using Time-resolved Fourier-transform Infrared Emission Spectroscopy}, year = {2020}, abstract = {

In photodissociation of trans-formic acid (HCOOH) at 193 nm, we have observed two molecular channels of CO + H2O and CO2 + H2 by using 1 μs-resolved Fourier-transform infrared emission spectroscopy. With the aid of spectral simulation, the CO spectra are rotationally resolved for each vibrational state (v = 1{\textendash}8). Each of the resulting vibrational and rotational population distributions is characteristic of two Boltzmann profiles with different temperatures, originating from either transition state pathway or OH-roaming to form the same CO + H2O products. The H2O roaming co-product is also spectrally simulated to understand the interplay with the CO product in the internal energy partitioning. Accordingly, this work has evaluated the internal energy disposal for the CO and H2O roaming products; especially the vibrational-state dependence of the roaming signature is reported for the first time. Further, given a 1 μs resolution, the temporal dependence of the CO/CO2 product ratio at v >= 1 rises from 3 to 10 of study, thereby characterizing the effect of conformational memory and well reconciling with the disputed results reported previously between absorption and emission methods. {\textcopyright} 2020, The Author(s).

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85082014259\&origin=inward\&txGid=b7d588eaa6743d6b52b474841485ab97}, author = {Tso, C.-J., Kasai, T., Lin, K.-C.} } @article {4331, title = {Sr-Doped NiO3 nanorods synthesized by a simple sonochemical method as excellent materials for voltammetric determination of quercetin}, year = {2020}, abstract = {

The simple and novel surfactant-free synthesis of flower-like strontium-doped nickel oxide nanorods (SNO NRs) via a simple sonochemical co-precipitation method was used for electrochemical sensing of quercetin (QCT). The structure and morphology of the as-synthesized flower-like SNO NRs were characterized using various spectroscopic techniques. Then, CV, EIS, and DPV were used to examine their electrochemical properties. The effective loading concentration, pH, scan rate and stability of the SNO NR-modified electrodes were studied. Under optimized conditions, the electrochemical detection of QCT demonstrated a low detection potential of 0.3 V (vs. Ag/AgCl), and achieved a higher oxidation peak current compared to those of other modified electrodes in PB (pH 5.0). The voltammetric current response was found to linearly increase with an increasing concentration range from 0.01-68.53 μM, along with a low detection limit of 1.98 nM, and a high sensitivity of 2.1055 μA mM cm-2. The sensor also shows good selectivity and satisfactory recovery for real sample (apple and grape juice) analysis. {\textcopyright} 2020 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85082989564\&origin=inward\&txGid=35280e4615a3f0ffcdb77671d4e72f5c}, author = {Vinothkumar, V., Sangili, A., Chen, S.-M., Veerakumar, P., Lin, K.-C.} } @article {4345, title = {Three-dimensional zinc oxide nanostars anchored on graphene oxide for voltammetric determination of methyl parathion}, year = {2020}, abstract = {

The two-step microwave method was used to synthesize zinc oxide nanostars linked to graphene oxide (GO) nanosheets. The material was used to modify a screen printed carbon electrode (SPCE) and then explored as a binder-free electrocatalyst for the electrochemical determination of methyl parathion (MP). The morphology and crystallinity of the material were characterized by various techniques. The modified SPCE shows extraordinary electrochemical performances for sensitive determination of MP. Figures of merit include (a) a wide linear dynamic range (0.03{\textendash}670 μM), (b) a low detection limit (1.2 nM; at S/N = 3), (c) a comparably low working voltage (-0.69 V vs. Ag/AgCl); and (d) an excellent sensitivity (16.5 μA μM-1 cm-2) that surpasses other modified electrodes. The sensor was successfully applied to the determination of MP, even in the presence of other common electroactive interference, in (spiked) fruits and vegetables. [Figure not available: see fulltext.]. {\textcopyright} 2019, Springer-Verlag GmbH Austria, part of Springer Nature.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85076264156\&origin=inward\&txGid=a38eacd2fe44831de0c22c6fa2fe5ca9} } @article {4339, title = {Ultrafine Bi-Sn nanoparticles decorated on carbon aerogels for electrochemical simultaneous determination of dopamine (neurotransmitter) and clozapine (antipsychotic drug)}, year = {2020}, abstract = {

This present study describes the synthesis of ultrafine Bi-Sn nanoparticles decorated on carbon aerogels (Bi-Sn NP/CAG) as a nanocomposite for the electrochemical simultaneous determination of dopamine (DA) and clozapine (CLZ). The typical characterization techniques, such as XRD, Raman, BET, FT-IR, TGA, XPS, and FE-SEM/TEM, showed useful insights into the crystal phase and morphology of Bi-Sn NP/CAG. Integrated Bi-Sn NP/CAG built into a cost-effective screen printed carbon electrode (SPCE) offers a high electrochemical surface area (ECSA) compared to unmodified, Bi-Sn, and CAG/SPCEs, such that it favourably allowed the binding of DA and CLZ molecules onto the surface at the Bi-Sn/CAG, which was demonstrated by cyclic and differential pulse voltammetry techniques. As a result, the DA and CLZ sensing exhibited low detection limits (DL, 4.6 and 97.6 nM (S/N = 3)), and sensitivity (3.402 and 0.4 μA μM-1 cm-2) over a wide linear range (0.02-97.59 and 0.5-2092 μM), respectively. To go a step further, the Bi-Sn NP/CAG/SPCE was applied for the simultaneous determination of DA and CLZ which featured lower DL (23.1 and 31.3 nM (S/N = 3)), and sensitivity (0.4979 and 0.04 μA μM-1 cm-2) over a wide linear range (2-182 and 10-910 μM), respectively. The selectivity for DA and CLZ in the presence of a 10-fold concentration of their potentially interfering active species was demonstrated. Finally, this sensing methodology enables the rapid electrochemical determination of the amount of DA and CLZ in a rat brain region serum sample with successful recovery outcomes. {\textcopyright} The Royal Society of Chemistry.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85096101466\&origin=inward\&txGid=8b924f8819392b86bfe9d2dc40360f30}, author = {Veerakumar, P., Manavalan, S., Chen, S.-M., Pandikumar, A., Lin, K.-C.} } @article {4338, title = {Ultrafine gold nanoparticle embedded poly(diallyldimethylammonium chloride)-graphene oxide hydrogels for voltammetric determination of an antimicrobial drug (metronidazole)}, year = {2020}, abstract = {

In this work, gold nanoparticle (Au NP) decorated poly(diallyldimethylammonium chloride) (PDDA) functionalized graphene hydrogel (Au NP@PDDA/GH) nanocomposites were fabricated. The resulting materials were characterized by a variety of analytical and spectroscopic techniques. Electrochemical performances of the prepared composites were examined by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and linear sweep voltammetry (LSV). The Au NPs were decorated uniformly and densely on the GO@PDDA composite material based on the electrostatic attraction and this new hierarchical nanostructure can provide a more favourable microenvironment for electron transfer. Under the optimized conditions, the Au NP@PDDA/GH nanocomposite was used as a novel sensing probe for metronidazole (MZ) which was found to have the concentration range of 0.4-656.4 μM with a correlation coefficient (0.999, limit of detection (LOD) based on (LOD = 3k/∂) of 0.097 μM), and a sensitivity of 4.286 μA μM-1. With satisfactory selectivity, reproducibility, and stability, the nanostructure we proposed offered an alternative for electrode fabrication and MZ sensing. Au NP@PDDA/GH was also applied to the reduction of MZ and pharmacy tablets by NaBH4under ambient conditions. Thus, Au NP@PDDA/GH application provides simplicity, reliability, durability, and low cost benefits. {\textcopyright} The Royal Society of Chemistry 2020.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85086315837\&origin=inward\&txGid=52a44c088381cc4ec6336b76034d574f}, author = {Veerakumar, P., Sangili, A., Chen, S.-M., Lin, K.-C.} } @article {4336, title = {UV Photodissociation of Halothane in a Focused Molecular Beam: Space-Speed Slice Imaging of Competitive Bond Breaking into Spin-Orbit-Selected Chlorine and Bromine Atoms}, year = {2020}, abstract = {

A molecular beam of halothane (2-bromo-2-chloro-1,1,1-trifluoroethane) is focused by a hexapolar electrostatic field and photolyzed by UV laser radiation at 234 nm. Angular and speed distributions of chlorine and bromine photofragments emitted from halothane are measured for both spin-orbit states independently. Although the dissociation energy of the C-Cl bond is larger than that of C-Br, the relative yield of Cl to Br was found to be approximately 2. Measured speed and angular distributions of atomic fragments show distinct kinetic energy release and scattering characteristics: for bromine, observed fast and aligned fragments exhibit a signature of a direct mode of dissociation for the C-Br bond, via the electronically excited potential energy surface denoted nσ*(C-Br), of repulsive nature; for chlorine, a variation in the features is observed for the dissociation pathway through nσ*(C-Cl), from a modality similar to the bromine case, leading to fragments with appreciable kinetic energy release and pronounced directionality, to a modality involving slow products, nearly isotopically distributed. The origin of this behavior can be attributed to nonadiabatic interaction operating between the nσ*(C-Br) and nσ*(C-Cl) surfaces. These results are not only relevant for a detailed understanding of adiabatic versus diabatic coupling mechanisms in the manifold of excited states populated by photon absorption, but they also point out the possibility of selectively inducing specific dissociation pathways, even when involving energetically unfavorable outcomes, such as, in this case, the prevailing rupture of the stronger C-Cl bond against that of the weaker C-Br bond. Copyright {\textcopyright} 2020 American Chemical Society.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85087531362\&origin=inward\&txGid=50a47f1933c616a76201259fd1983ab3}, author = {Che, D.-C., Nakamura, M., Chang, H.-P., Lin, K.-C., Kasai, T., Aquilanti, V., Palazzetti, F.} } @article {4041, title = {Binder-Free Modification of a Glassy Carbon Electrode by Using Porous Carbon for Voltammetric Determination of Nitro Isomers}, journal = {ACS Omega}, volume = {4}, year = {2019}, pages = {8907-8918}, abstract = {

In this study, Liquidambar formosana tree leaves have been used as a renewable biomass precursor for preparing porous carbons (PCs). The PCs were produced by pyrolysis of natural waste of leaves after 10\% KOH activation under a nitrogen atmosphere and characterized by a variety of state-of-the-art techniques. The PCs possess a large surface area, micro-/mesoporosity, and functional groups on its surface. A glassy carbon electrode modified with high PCs was explored as an efficient binder-free electrocatalyst material for the voltammetric determination of nitro isomers such as 3-nitroaniline (3-NA) and 4-nitroaniline (4-NA). Under optimal experimental conditions, the electrochemical detection of 3-NA and 4-NA was found to have a wide linear range of 0.2-115.6 and 0.5-120 μM and a low detection limit of 0.0551 and 0.0326 μM, respectively, with appreciable selectivity. This route not only enhanced the benefit from biomass wastes but also reduced the cost of producing electrode materials for electrochemical sensors. Additionally, the sensor was successfully applied in the determination of nitro isomers even in the presence of other common electroactive interference and real samples analysis (beverage and pineapple jam solutions). Therefore, the proposed method is simple, rapid, stable, sensitive, specific, reproducible, and cost-effective and can be applicable for real sample detection. {\textcopyright} 2019 American Chemical Society.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85066074731\&doi=10.1021\%2facsomega.9b00622\&origin=inward\&txGid=6cf8499a8a44d893d52312765e6164b0}, author = {Manavalan, S. and P. Veerakumar and Chen, S.-M. and Murugan, K. and King-Chuen Lin} } @article {4037, title = {Catalytic Activity of Bimetallic (Ruthenium/Palladium) Nano-alloy Decorated Porous Carbons Toward Reduction of Toxic Compounds}, journal = {Chemistry - An Asian Journal}, volume = {14}, year = {2019}, pages = {2662-2675}, abstract = {

Chicken feather-derived high-surface-area porous activated carbon (CFAC) material was prepared using chemical activation. A new composite composed of Ru-Pd nanoparticles supported on CFAC (Ru-Pd@CFAC) has been prepared by microwave-thermal reduction in the presence of the support. Characterization by XRD, Raman, BET, FE-SEM/TEM, FT-IR, TGA, XPS, HAADF-STEM-EDS, H2-chemisorption, H2-TPR, and ICP-AES was used to analyze the catalyst. This catalyst is found to be efficient for the reduction of hexavalent chromium (CrVI), potassium ferricyanide (K3[Fe(CN)6]), 4-nitrophenol (4-NP), and pendimethalin (PDM), at room temperature, and remains stable, even after several repeated runs. Moreover, it showed excellent catalytic activity compared with the monometallic counterparts. {\textcopyright} 2019 Wiley-VCH Verlag GmbH \& Co. KGaA, Weinheim

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85068614040\&doi=10.1002\%2fasia.201900350\&origin=inward\&txGid=4fb0d499892fdf9ffc001eb47e15ba66}, author = {P. Veerakumar and Salamalai, Kamaraj and Dhenadhayalan, Namasivayam and King-Chuen Lin} } @article {4035, title = {Fluorescence turn-on chemosensors based on surface-functionalized MoS2 quantum dots}, journal = {Sensors and Actuators, B: Chemical}, volume = {281}, year = {2019}, pages = {659-669}, abstract = {

The multiple sensing capabilities of molybdenum disulfide quantum dots (MoS2 QDs) towards metal ions were scrutinized by tuning their surface functional groups. The MoS2 QDs surface was individually modified with thiol-containing capping agents to form carboxylic-, amine- and thiol-functionalized MoS2 QDs (MoS2/COOH, MoS2/NH2 and MoS2/SH) by the facile hydrothermal method. Each as-prepared QDs exhibits strong excitation wavelength dependent fluorescence behavior. The design of MoS2 QDs based metal ion sensor was implemented based on the fluorescence turn-on mechanism. These MoS2/COOH, MoS2/NH2 and MoS2/SH QDs sensors exhibit superior performance towards the highly selective detection of Co2+, Cd2+ and Pb2+ ions, respectively, due to the varied association of each functional group towards metal ions. The resultant detection limit of Co2+, Cd2+ and Pb2+ was evaluated to be 54.5, 99.6 and 0.84 nM, respectively, and the related fluorescence turn-on mechanism is verified unambiguously. The binding energies were calculated for QDs with metal ions pairs and the results lent support to the determined sensitivity. The as-prepared QDs were also successfully demonstrated to detect the above metal ions in real water samples. While becoming potential candidates in the chemosensors based on the fluorescence probe, these surface modified MoS2 QDs can offer an excellent sensing capability for specific metal ions with extremely high selectivity.

}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85056173424\&doi=10.1016\%2fj.snb.2018.11.009\&partnerID=40\&md5=a862b5eb2b07c4b1160a9606032f69b3}, author = {T.-W. Lin and Dhenadhayalan, N. and Lee, H.-L. and Lin, Y.-T. and King-Chuen Lin and A.H.H. Chang} } @article {4042, title = {Functionalized Mesoporous Carbon Nanostructures for Efficient Removal of Eriochrome Black-T from Aqueous Solution}, journal = {Journal of Chemical and Engineering Data}, volume = {64}, year = {2019}, pages = {1305-1321}, abstract = {

Acid-functionalized mesoporous carbons (AF-MPCs) have been synthesized and used as adsorbents for removal of an azo dye, Eriochrome Black-T (EBT), from aqueous solution. To generate acid surface functionalities, mesoporous carbons (MPCs) were treated with sulfuric acid. Characterization of the samples was analyzed by XRD, Raman spectra, N 2 adsorption-desorption, FE-TEM, TGA, and FT-IR studies. The adsorption studies were carried out under various parameters, such as pH, adsorbent dosage, contact time, initial dye concentration solution temperature, and salt concentration. The results showed that the EBT adsorption onto samples was affected by the pH of solution; the maximum EBT ion adsorption took place at pH 1; and the adsorption uptake was increased with an increase in the initial dye concentration. Moreover, the mechanism of adsorption was investigated using kinetic, diffusion, and isotherm models. The best fit was obtained by the Langmuir model with high correlation coefficients (R 2 = 0.9463) with a maximum monolayer adsorption capacity of 117.0 mg{\textperiodcentered}g -1 . The adsorbed anionic EBT dye molecules were eluted by ethanol solvent with the recovery percentage of 98\%. Moreover, this study demonstrates that AF-MPCs can be successfully used as a low-cost adsorbent for the removal of EBT from aqueous solutions. {\textcopyright} 2019 American Chemical Society.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85063146392\&doi=10.1021\%2facs.jced.8b00878\&origin=inward\&txGid=d8575394519f01ea73d1975571762ff5}, author = {P. Veerakumar and Tharini Jeyapragasam and Surabhi, S. and Salamalai, Kamaraj and Maiyalagan, T. and King-Chuen Lin} } @article {4040, title = {Multifunctional Nanohybrid of Palladium Nanoparticles Encapsulated by Carbon-Dots for Exploiting Synergetic Applications}, journal = {Advanced Materials Interfaces}, volume = {6}, year = {2019}, abstract = {

Palladium nanoparticles encapsulated in the carbon dots (Pd/C-dots) are demonstrated to play a role of multifunctional nanohybrid in the synergetic applications of sensor and catalysis. The photochemical method is applied to synthesize Pd/C-dots in which Pd nanoparticles (NPs) are dispersedly encapsulated by C-dots layer. The nanohybrid can function as a fluorescent sensor and reductive catalyst, due to the inherent properties of C-dots and Pd NPs, respectively. The Pd/C-dots exhibit a highly selective and sensitive detection toward the nickel (Ni2+) ion with a detection limit of 7.26 {\texttimes} 10-9 m. Moreover, the Ni2+ is detected in MCF-7 live cells signifying the applicability of nanohybrid as a promising sensor. On the other hand, the Pd/C-dots show an excellent catalytic performance in the reduction of 4-nitrophenol and eosin yellow. A plausible mechanism for sensing and catalysis behavior is proposed. The sensor system is designed on the basis of the fluorescence turn-on when Ni2+ interacts with functional groups of the C-dots layer. The activities of catalytic reduction are mainly governed by the Pd NPs and further enhanced when the C-dots layer is incorporated. The Pd/C-dots can serve as a new paradigm for opening a potential trend in the design of multifunctional materials to diverse applications. {\textcopyright} 2019 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85066138893\&doi=10.1002\%2fadmi.201900361\&origin=inward\&txGid=573f68cca2f1028084ba702f0b3455ca}, author = {Dhenadhayalan, Namasivayam and Hsin, T.-H. and King-Chuen Lin} } @article {4034, title = {Photodissociation of CH2BrI using cavity ring-down spectroscopy: in search of a BrI elimination channel}, journal = {Physical Chemistry Chemical Physics}, volume = {21}, year = {2019}, pages = {13943-13949}, abstract = {

Photodissociation of CH2BrI was investigated in search of unimolecular elimination of BrI via a primary channel using cavity ring-down absorption spectroscopy (CRDS) at 248 nm. The BrI spectra were acquired involving the first three ground vibrational levels corresponding to A3Π1 {\textleftarrow} X1Σ+ transition. With the aid of spectral simulation, the BrI rotational lines were assigned. The nascent vibrational populations for v'' = 0, 1, and 2 levels are obtained with a population ratio of 1:(0.58 {\textpm} 0.10):(0.34 {\textpm} 0.05), corresponding to a Boltzmann-like vibrational temperature of 713 {\textpm} 49 K. The quantum yield of the ground state BrI elimination reaction is determined to be 0.044 {\textpm} 0.014. The CCSD(T)//B3LYP/MIDI! method was employed to explore the potential energy surface for the unimolecular elimination of BrI from CH2BrI.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85068503890\&doi=10.1039\%2fc8cp04130j\&origin=inward\&txGid=7fc601f269b93a6934e081b9c9354299}, author = {Muthiah, B. and Paredes-Roib{\'a}s, D. and Kasai, T. and King-Chuen Lin} } @article {4043, title = {Pyrene-based prospective biomaterial: In vitro bioimaging, protein binding studies and detection of bilirubin and Fe3+}, journal = {Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy}, volume = {211}, year = {2019}, abstract = {

Herein, we have meticulously derived the nanosized fluorescent aggregates from pyrene Schiff base (PS) in DMSO:water (10:90) ratio. The aggregation property of PS molecule was characterized by SEM and TEM measurements, revealed the aggregated particles are in spherical shape with ~3 nm in size. Moreover, aggregates exhibit a high fluorescence quantum yield (48\%) which was effectively used for the in vitro bioimaging of two different cancer cells such as A549 and MCF-7 cells in which it exhibiting excellent biocompatibility. Further, it was estimated the capability of twofold acridine orange/ethidium bromide (AO/EB) staining to identify the apoptotic associated changes in cancer cells. Additionally, the aggregates were successfully demonstrated as a luminescent probe for the perceptive biomolecule detection of bilirubin. On the other hand, the PS molecule was successfully utilized for protein binding and metal ion sensing studies. The interaction of bovine serum albumin (BSA) with PS molecule in DMSO was using fluorescence spectroscopic method and nature of interaction was also confirmed through molecular docking analysis. The PS molecule also acts as an excellent sensor for biologically important Fe3+ ion with detection limit of 336 nM. Overall, PS molecule can be a prospective material in biological field both in solution as well as aggregated forms. {\textcopyright} 2019 Elsevier B.V.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85066634052\&doi=10.1016\%2fj.saa.2019.117150\&origin=inward\&txGid=e6893198b8c363beb119a4050128ddf8}, author = {Srinivasan, Venkatesan and Jhonsi, Mariadoss Asha and King-Chuen Lin and Ananth, D.A. and Sivasudha,T. and Narayanaswamy, R. and Kathiravan, Arunkumar} } @article {4039, title = {Stereodynamic Imaging of Bromine Atomic Photofragments Eliminated from 1-Bromo-2-methylbutane Oriented via Hexapole State Selector}, journal = {Journal of Physical Chemistry A}, volume = {123}, year = {2019}, pages = {6799-6811}, abstract = {

Both single-laser and two-laser experiments were conducted to look into the ion-imaging of Br*(2P1/2) and Br(2P3/2) photofragmented from 1-bromo-2-methylbutane in the range 232-240 nm via a detection scheme of (2+1) resonance-enhanced multiphoton ionization. The angular analysis of these photofragment distributions yields the anisotropy parameter β = 1.88 {\textpm} 0.06 for the Br* excited state which arises from a parallel transition, while β = 0.63 {\textpm} 0.09 for the Br ground state indicates the contribution from both a perpendicular transition and a non-adiabatic transition. When a hexapole coupled with an orienting field was implemented, the parent molecules are spatially oriented to yield an orientation efficiency |{\guillemotleft}cos θ {\guillemotright}| of 0.15. Besides the χ angle between the recoil velocity v and the transition dipole moment μ, orienting molecules allows for the evaluation of the angle α between v and the permanent molecular dipole moment d. The angular analysis of Br* photofragment distribution yields χ = 11.5{\textdegree} and α in the range from 160{\textdegree} to 180{\textdegree} with weak dependency. In the two-laser experiments, the angular anisotropy of Br photofragment distribution was found to be smaller (0.38 {\textpm} 0.10) when the photolysis wavelength was red-shifted to 240 nm, suggesting the increasing contributions from perpendicular transitions. {\textcopyright} 2019 American Chemical Society.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85068061488\&doi=10.1021\%2facs.jpca.9b04048\&origin=inward\&txGid=5f2a0577b811d506098f1d89c91fd11f}, author = {Nakamura, M. and Chang, H.-P. and King-Chuen Lin and Kasai, Toshio and Che, Dock-Chil and Palazzetti, Federico and Aquilanti, Vincenzo} } @article {4038, title = {Vectorial imaging of the photodissociation of 2-bromobutane oriented: Via hexapolar state selection}, journal = {Physical Chemistry Chemical Physics}, volume = {21}, year = {2019}, pages = {14164-14172}, abstract = {

Molecular orientation techniques are becoming available in the study of elementary chemical processes, in order to highlight those structural and dynamical properties that would be concealed by random rotational motions. Recently successful orientation was achieved for asymmetric-top and chiral molecules of much larger complexity than hitherto. In this work, we report and discuss the correlation between the vectors{\textquoteright} photofragment recoil velocity v, transition dipole moment μ, and permanent dipole moment d in a dissociation experiment on hexapole oriented 2-bromobutane, photoinitiated by a linearly polarized laser. The sliced ion images of the Br*(2P1/2) and Br(2P3/2) photofragments were acquired at 234.0 and 254.1 nm, respectively, by a (2 + 1) resonance-enhanced multiphoton ionization technique. A detailed analysis of the sliced ion images obtained at a tilting angle 45{\textdegree} of laser polarization provides information on the correlation of the three vectors, which are confined by two polar angles α and χ and one azimuthal angle φμd in the recoil frame. The sliced ion images of Br fragments eliminated individually from the enantiomers at 254.1 nm yield an asymmetric factor close to zero; for this reason the photofragment angular distributions do not show significant differences. The elimination of the Br* fragment at 234.0 nm is mainly correlated with a parallel transition, giving rise to a large anisotropy parameter of 1.85, and thus can be considered as a single state excitation. The resulting recoil frame angles are optimized to 163{\textdegree} {\textpm} 8{\textdegree} and 164{\textdegree} {\textpm} 1{\textdegree} for α and χ, respectively, whereas φμd is approaching 0{\textdegree} for the best fit. Since for the present molecule, the three vectors have an only slight spatial arrangement, the photofragment angular distributions of the two enantiomers do not show appreciable differences. Theoretical and computational simulations provide us the basis to state that oriented enantiomers can be discriminated on-the-fly in photodissociation processes even initiated by non-circularly polarized light, provided that the three vectors encountered above have specific three-dimensional arrangements. The fact that Br fragment elimination involves a multi-potential dissociation carries uncertainties in theoretical estimates of the vector direction. Therefore, this work represents a preliminary but significant step on the road to chiral discrimination on-the-fly, which is shown to be best propitiated in molecules where vectors are far from having degenerate mutual angular directions. {\textcopyright} 2019 the Owner Societies.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85068090336\&doi=10.1039\%2fc8cp04270e\&origin=inward\&txGid=eabdc88e8cfd9ebf437f013717ebd3e9}, author = {Nakamura, Masaaki and Palazzetti, Federico and Tsai, P.-Y. and King-Chuen Lin and Kasai, Toshio and Che, D.-C. and Lombardi, Andrea and Aquilanti, Vincenzo} } @article {4036, title = {Voltammetric determination of vitamin B2 by using a highly porous carbon electrode modified with palladium-copper nanoparticles}, journal = {Microchimica Acta}, volume = {186}, year = {2019}, pages = {299}, abstract = {

Palladium-copper nanoparticles were placed on activated carbon to give a nanocomposite for electrochemical sensing of riboflavin (vitamin B 2 ). The activated carbon was produced by pyrolysis of natural waste of pistachio nutshells after KOH activation and under a nitrogen atmosphere. The carbons possess a large surface area and micro/meso-porosity. The nanocomposite was characterized by a variety of techniques to confirm structures and morphology. A screen-printed electrode modified with the composite was examined by EIS, CV, DPV, and amperometry. The effects of pH value, scan rate, and stability of the modified electrode were studied. Under optimized conditions, vitamin B 2 displays a well-expressed oxidation peak at -0.15 V (vs. Ag/AgCl) in solutions with a pH value of 7.0. The voltammetric signal increases linearly in the 0.02 to 9 μM concentrations range and a lower detection limit of 7.6 pM. The sensor was successfully applied to the determination of vitamin B 2 even in the presence of other common vitamins and in (spiked) raw milk samples. [Figure not available: see fulltext.]. {\textcopyright} 2019, Springer-Verlag GmbH Austria, part of Springer Nature.

}, url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-85064939998\&doi=10.1007\%2fs00604-019-3396-7\&origin=inward\&txGid=e530c3961a142422cb507e392de01ccb}, author = {Sangili, A. and P. Veerakumar and Chen, S.-M. and Rajkumar, C. and King-Chuen Lin} } @article {doi:10.1002/cnma.201800353, title = {Metal Nanoparticles Anchored on Rhenium Disulfide Nanosheets as Catalysts for the Reduction of Aromatic Nitro Compounds}, journal = {ChemNanoMat}, year = {2018}, note = {

n/a

}, abstract = {

Abstract The nanohybrids of noble metal (M=Ag, Au, Pd, Pt, and Ru) nanoparticle-decorated rhenium disulfide nanosheets (ReS2 NSs) were demonstrated as excellent catalysts towards the reduction of aromatic nitro compounds. The M/ReS2 nanohybrids were synthesized by facile hydrothermal method and characterization results proved that each metal nanoparticle was anchored on the ReS2 NSs. These nanohybrids exhibited superior catalytic performance towards the reduction of aromatic nitro compounds including 4-nitrophenol, 2-nitroaniline, and nitrobenzene. Interestingly, the Ru/ReS2 and Pd/ReS2 showed enhanced catalytic reduction compared to Ag/ReS2, Au/ReS2, and Pt/ReS2 and also showed significant catalytic stability due to metal nanoparticles anchored strongly on the surface of ReS2 NSs. Moreover, these M/ReS2 nanohybrids turned out to have much better catalytic performance compared to noble metal nanoparticle-based catalysts. A plausible reduction mechanism was proposed for each nitro compound. It was verified that the metal-nanoparticle-mediated hydrogen transfer was involved in the reduction of nitro compounds to amines. This report demonstrates the catalytic activities for metal nanoparticle-decorated ReS2 nanohybrids, which can serve as a paradigm to open up a future trend in the design of transition metal dichalcogenides nanohybrids as superior catalysts.

}, keywords = {heterogeneous catalysis, NANOPARTICLES, nitro compounds, reduction, Transition metal dichalcogenides}, doi = {10.1002/cnma.201800353}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/cnma.201800353}, author = {Dhenadhayalan, Namasivayam and Lin, Ta-Wei and Pitchaimani Veerakumar and King-Chuen Lin} } @article {Veerakumar2018433, title = {Activated porous carbon supported rhenium composites as electrode materials for electrocatalytic and supercapacitor applications}, journal = {Electrochimica Acta}, volume = {271}, year = {2018}, note = {

cited By 4

}, pages = {433-447}, abstract = {

In this study, we developed highly dispersed rhenium nanoparticles decorated on activated carbon (Re@CDACs). The activated carbons were derived from the biomass raw materials cardamom pods (Elettaria cardamomum L) via carbonization followed by activation with ZnCl2 at high temperature. The Re NPs synthesis was achieved by decomposition of [Re2(CO)10] complex via a facile microwave thermal reduction technique. The as-prepared Re@CDACs nanocomposites were characterized by a combination of state-of-the-art techniques. The Re@CDACs nanocomposites so prepared were utilized for electrocatalytic oxidation of sunset yellow (SY) and supercapacitor applications. The Re@CDACs-modified electrodes were found to show extraordinary electrochemical performance for sensitive and selective detection of SY with a wide linear range of 0.05{\textendash}390 μM and a detection limit and sensitivity of 16 nM (S/N = 3) and 91.53 μA μM-1, respectively, surpassing other modified electrodes. Moreover, these Re@CDACs catalysts were also found to exhibit a higher specific capacitance of 181 F g-1 at a current density of 1.6 A g-1 in 1.0 M H2SO4 electrolyte. The specific capacitance retention of 90\% was achieved after 2500 cycles at current density 2.0 A g-1. Therefore, we have demonstrated that the Re@CDACs nanocomposite materials could be used as a promising electrode material in electrochemical oxidation of SY and energy storage applications. {\textcopyright} 2018

}, keywords = {Activated carbon, Capacitance, Carbonization, Chlorine compounds, Electro-catalytic oxidation, Electrocatalysis, Electrochemical electrodes, Electrochemical oxidation, Electrochemical performance, Electrolytes, Energy storage applications, Nanocomposites, Porous materials, Rhenium compounds, Rhenium oxide, Specific capacitance, State-of-the-art techniques, Sunset yellows, SUPERCAPACITOR, Supercapacitor application, Zinc chloride}, doi = {10.1016/j.electacta.2018.03.165}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85051658063\&doi=10.1016\%2fj.electacta.2018.03.165\&partnerID=40\&md5=411f7be02eb6fd3949aa45813df38531}, author = {P. Veerakumar and Rajkumar, C. and Chen, S.-M. and Thirumalraj, B. and Lin, K.-C.} } @article {Dhenadhayalan2018929, title = {Aptamer-based fluorogenic sensing of interferon-gamma probed with ReS2 and TiS2 nanosheets}, journal = {Sensors and Actuators, B: Chemical}, volume = {258}, year = {2018}, note = {

cited By 0

}, pages = {929-936}, abstract = {

The fluorogenic aptamer sensing of interferon-gamma (IFN-γ) was scrutinized using two-dimensional (2D) ReS2 and TiS2 nanosheets (NSs) as a platform. The IFN-γ an important cytokine, functions as a bio-indicator to detect infectious diseases such as tuberculosis and human immunodeficiency virus. This 2D NSs based aptamer sensor was implemented to induce the fluorescence off/on resulting from an aptamer, in the absence or presence of a target to be probed. The fluorescence emitting from the aptamer is quenched by interacting with NSs, while the ensuing fluorescence is recovered upon addition of target. Such a fluorescence off/on mechanism was proposed based on the behavior of fluorescence resonance energy transfer (FRET) between the aptamer and NSs. The fluorescence response exhibits linearity as a function of target, and the detection limit of IFN-γ was evaluated to be 57.6 and 82.7 pM for ReS2 and TiS2 NSs, respectively, being comparable to or even better than those methods adopted for probing IFN-γ. The selectivity property was also characterized with various targets, exhibiting a very specific selectivity for IFN-γ. The findings reveal that the aptamer-transition metal dichalcogenides (TMD) NSs will be a great sensing pair to the development of aptamer-based biosensors. Moreover, the biocompatibility and sensing capability of IFN-γ was implemented in human embryonic kidney 293T (HEK) live cells. This is the first report to emerging fluorogenic sensing of IFN-γ aptamer with 2D TMD, showing a promising trend for future design of biosensors. {\textcopyright} 2017 Elsevier B.V.

}, keywords = {Antibiotics, Aptamers, Biocompatibility, Biosensors, Diseases, Energy transfer, Fluorescence, Fluorescence Resonance Energy Transfer, Glycoproteins, Human embryonic kidneys, Human immunodeficiency virus, Interferon-gamma, NANOSHEETS, Rhenium compounds, Specific selectivity, Titanium compounds, Transition metal dichalcogenides (TMD), Transition metals, Two Dimensional (2 D), Viruses}, doi = {10.1016/j.snb.2017.11.178}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85036647797\&doi=10.1016\%2fj.snb.2017.11.178\&partnerID=40\&md5=d46150b3d1fe9172a9607b8856b334ae}, author = {Dhenadhayalan, N. and Sriram, M.I. and Lin, K.-C.} } @article {Paredes-Roib{\'a}s20188344, title = {Cavity Ring-Down Absorption Spectroscopy: Optical Characterization of ICl Product in Photodissociation of CH2ICl at 248 nm}, journal = {Journal of Physical Chemistry A}, volume = {122}, number = {42}, year = {2018}, note = {

cited By 0

}, pages = {8344-8353}, abstract = {

Iodine monochloride (ICl) elimination from one-photon dissociation of CH2ICl at 248 nm is monitored by cavity ring-down absorption spectroscopy (CRDS). The spectrum of ICl is acquired in the transition of B3 0X1 + and is confirmed to result from a primary photodissociation, that is, CH2ICl + h{\textrightarrow}CH2 + ICl. The vibrational population ratio is determined with the aid of spectral simulation to be 1:(0.36 {\textpm} 0.10):(0.11 {\textpm} 0.05) for the vibrational levels = 0, 1, and 2 in the ground electronic state, corresponding to a Boltzmann-like vibrational temperature of 535 {\textpm} 69 K. The quantum yield of the ICl molecular channel for the reaction is obtained to be 0.052 {\textpm} 0.026 using a relative method in which the scheme CH2Br2 {\textrightarrow}CH2 + Br2 is adopted as the reference reaction. The ICl product contributed by the secondary collisions is minimized such that its quantum yield obtained is not overestimated. With the aid of the CCSD(T)//B3LYP/MIDI! level of theory, the ICl elimination from CH2ICl is evaluated to follow three pathways via either (1) a three-center transition state or (2) two isomerization transition states. However, the three-center concerted mechanism is verified to be unfavorable. {\textcopyright} 2018 American Chemical Society.

}, keywords = {Absorption spectroscopy, Bromine compounds, Chlorine compounds, Concerted mechanism, Ground electronic state, Iodine monochloride, Light measurement, Molecular channels, Optical characterization, Photodissociation, quantum theory, Quantum yield, Spectral simulations, Vibrational population, Vibrational temperature}, doi = {10.1021/acs.jpca.8b07012}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85055121067\&doi=10.1021\%2facs.jpca.8b07012\&partnerID=40\&md5=5721a771a84de872f8436491c7016037}, author = {Paredes-Roib{\'a}s, D. and Balaganesh, M. and Kasai, T. and Gavira-Vallejo, J.M. and K.C. Lin} } @article {Veerakumar2018354, title = {Low-cost palladium decorated on: M -aminophenol-formaldehyde-derived porous carbon spheres for the enhanced catalytic reduction of organic dyes}, journal = {Inorganic Chemistry Frontiers}, volume = {5}, number = {2}, year = {2018}, note = {

cited By 2

}, pages = {354-363}, abstract = {

We report the use of palladium nanoparticles (Pd NPs) immobilized on m-aminophenol/formaldehyde resin (APF)-derived porous carbon spheres (Pd@PCS) as heterogeneous catalysts for the reduction of organic dyes. The morphology, structure, surface compositions, and textural properties of PCS and the Pd@PCS catalyst were characterized fully to document the excellent catalytic efficiency of Pd@PCS composites. Pd NPs of mean particle size ca. 12 {\textpm} 0.8 nm were highly dispersed on the surface of PCSs, and possessed surface area and pore volume as high as 896.3 m2 g-1 and 0.934 cm3 g-1, respectively. Prepared catalysts were applied to the reduction of various organic dyes; high catalytic activity towards crystal violet, eosin yellow and sunset yellow was observed. More importantly, the catalysts could be recovered readily, and reused many times with good stability. Therefore, the robust material utilized for the treatment of containing organic dyes could be used widely for environmental applications. {\textcopyright} 2018 the Partner Organisations.

}, doi = {10.1039/c7qi00553a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85042119676\&doi=10.1039\%2fc7qi00553a\&partnerID=40\&md5=0cc0a47bc5ec47d1ebea33853a2fff0c}, author = {P. Veerakumar and Panneer Muthuselvam, I. and Thanasekaran, P. and Lin, K.-C.} } @article {Veerakumar2018, title = {Paper flower-derived porous carbons with high-capacitance by chemical and physical activation for sustainable applications}, journal = {Arabian Journal of Chemistry}, year = {2018}, note = {

cited By 0; 待刊論文

}, abstract = {

Porous carbon nanosheets were prepared by the carbonization of paper flower via chemical and physical activation. The structural properties of the as-prepared carbons were characterized using the techniques, such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Raman spectroscopy, N2 sorption isotherms and X-ray photoelectron spectroscopy (XPS), while the related morphological analyses were conducted using scanning/transmission electron microscopy (SEM/TEM). The obtained carbons exhibit a high specific surface area up to 1801 m2 g-1 with a robust porous graphitic carbon layer structure, which provides the merits for potential application in energy storage and dye removal. We carried out potentiostatic and galvanostatic measurements using a three-electrode cell in 1.0 M H2SO4 aqueous electrolyte and achieved a specific capacitance of 118, 109.5, 101.7, 93.6, and 91.2 F g-1 at 1, 2, 4, 8 and 12 A g-1, respectively. The stability at 12 A g-1 was tested to reach 10,000 cycles with capacity retention of around 97.4\%. We have demonstrated that the paper flower-derived carbons at activation temperature 800 {\textdegree}C (PFC-800) can be used as a promising electrode material in supercapacitor. PFC-800 can also serve as an efficient sunset yellow dye removal, showing the maximum adsorption capacity for sunset yellow (Q0, 273.6 mg g-1). {\textcopyright} 2018 King Saud University

}, keywords = {Activation temperatures, ADSORPTION, Adsorption capacities, Capacitance, carbon, Carbonization, Chemical activation, Electrodes, Electrolytes, Fourier transform infra red (FTIR) spectroscopy, Fourier transform infrared spectroscopy, High specific surface area, Porous carbons, Porous graphitic carbon, Porous materials, Potentiostatic and galvanostatic measurements, Scanning electron microscopy, Sunset yellows, SUPERCAPACITOR, X ray photoelectron spectroscopy}, doi = {10.1016/j.arabjc.2018.08.009}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85052750563\&doi=10.1016\%2fj.arabjc.2018.08.009\&partnerID=40\&md5=544ac010c4b235c8cf8dde3ae4432132}, author = {P. Veerakumar and Maiyalagan, T. and Raj, B.G.S. and Guruprasad, K. and Jiang, Z. and Lin, K.-C.} } @article {Kasai2018219, title = {Roaming and chaotic behaviors in collisional and photo-initiated molecular-beam reactions: a role of classical vs. quantum nonadiabatic dynamics}, journal = {Rendiconti Lincei}, volume = {29}, number = {2}, year = {2018}, note = {

cited By 0

}, pages = {219-232}, abstract = {

A new reaction scheme is proposed to account for roaming and chaotic behaviors in collisional and photo-initiated molecular-beam reactions, where nonadiabatic dynamics plays a key role and the collapse of superposition of wave functions is considered to be important in the beginning of the present scheme. Since the feature of molecular orbitals of reagents is crucial in reaction, we showed how to map out the spatial distribution of the relevant HOMO molecular orbitals of CH3Cl in the impact of fast electrons. We identified by experiment that the multiple overlap of nearby molecular orbitals affects even the vibrational motion of adjacent molecule DCl of the transient [ClDCl] chemical species. We also showed dynamical steric effects in the HBr + OH four-atom reaction as a manifestation of the nonadiabatic dynamics in complex systems. The roaming mechanism in the photo-initiated reaction of methyl formate is clarified in detail by experiment as well as the QCT trajectory calculation, where the conical intersection region plays an essential role. We suggest that two types of roaming trajectories coexist, i.e., deterministic and chaotic roaming trajectories based on classical trajectory calculations. To clarify the nonadiabatic dynamics in the roaming mechanism for non-collinear three-dimensional (3D) collisions, a new model of the 3D Polanyi rule is proposed as the extension of the well-established 2D Polanyi rule. In the 3D Polanyi rule, it is expected that the curvature and torsion of Frenet{\textendash}Serret formulas in three-dimensional space would provide us key concepts in understanding reaction dynamics. {\textcopyright} 2018, Accademia Nazionale dei Lincei.

}, keywords = {3D Polanyi rule in non-collinear collisions, Bromine compounds, Chemical reactions, Chlorine compounds, Collapse of superposition, Conical intersection, DYNAMICS, Molecular beams, Molecular orbitals, Multiple interactions, Non-adiabatic dynamics, OH reaction, Trajectories, Wave functions}, doi = {10.1007/s12210-018-0709-4}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85047161653\&doi=10.1007\%2fs12210-018-0709-4\&partnerID=40\&md5=e6cf000d2509a1c67e43e5a519ae02f1}, author = {Kasai, T. and Che, D.-C. and Tsai, P.-Y. and Nakamura, M. and Muthiah, B. and Lin, K.-C.} } @article {Lin2018217, title = {Roaming signature in photodissociation of carbonyl compounds}, journal = {International Reviews in Physical Chemistry}, volume = {37}, number = {2}, year = {2018}, note = {

cited By 0

}, pages = {217-258}, abstract = {

An alternative to the transition state (TS) pathway, the roaming route, which bypasses the minimum energy path but produces the same molecular products, was recently found in photodissociation dynamics. This account describes signatures of roaming in photodissociation of the carbonyl compounds, specifically methyl formate and aliphatic aldehydes. Methyl formate was promoted to the excited state, followed by internal conversion via a conical intersection. Then, the energetic precursor dissociated to fragments which proceeded along either TS or roaming path. In contrast to the lack of a roaming saddle point found in methyl formate, the structure of the roaming saddle point for each of a series of aliphatic aldehydes comprises two moieties that are weakly bound at a distance. As its size increases, the energy difference between the TS barrier and the roaming saddle point increases and the roaming pathway becomes increasingly dominant. Experimentally, the rotational-level dependence of the roaming route was measured with ion imaging, while the vibrational-state dependence was observed with time-resolved Fourier-transform infrared emission spectroscopy. The roaming signature was verified theoretically by quasi-classical trajectory (QCT) calculations. As an alternative to the QCT method, a multi-center impulsive model was developed to simulate the roaming scalar and vector properties. {\textcopyright} 2018 Informa UK Limited, trading as Taylor \& Francis Group.

}, doi = {10.1080/0144235X.2018.1488951}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85055106861\&doi=10.1080\%2f0144235X.2018.1488951\&partnerID=40\&md5=ae1a63b804acd35310b95201f078eedb}, author = {Lin, K.-C. and Tsai, P.-Y. and Chao, M.-H. and Nakamura, M. and Kasai, T. and Lombardi, A. and Palazzetti, F. and Aquilanti, V.} } @article {Veerakumar201812609, title = {Simple Preparation of Porous Carbon-Supported Ruthenium: Propitious Catalytic Activity in the Reduction of Ferrocyanate(III) and a Cationic Dye}, journal = {ACS Omega}, volume = {3}, number = {10}, year = {2018}, note = {

cited By 0

}, pages = {12609-12621}, abstract = {

The present study involves the synthesis, characterization, and catalytic application of ruthenium nanoparticles (Ru NPs) supported on plastic-derived carbons (PDCs) synthesized from plastic wastes (soft drink bottles) as an alternative carbon source. PDCs have been further activated with CO2 and characterized by various analytical techniques. The catalytic activity of Ru@PDC for the reduction of potassium hexacyanoferrate(III), (K3[Fe(CN)6]), and new fuchsin (NF) dye by NaBH4 was performed under mild conditions. The PDCs had spherical morphology with an average size of 0.5 μm, and the Ru NP (5 {\textpm} 0.2 nm) loading (4.01 wt \%) into the PDC provided high catalytic performance for catalytic reduction of ferrocyanate(III) and NF dye. This catalyst can be recycled more than six times with only a minor loss of its catalytic activity. In addition, the stability and reusability of the Ru@PDC catalyst are also discussed. Copyright {\textcopyright} 2018 American Chemical Society.

}, doi = {10.1021/acsomega.8b01680}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85054544631\&doi=10.1021\%2facsomega.8b01680\&partnerID=40\&md5=2897101c670fa19836efd65eccab0d8d}, author = {P. Veerakumar and Salamalai, K. and Thanasekaran, P. and Lin, K.-C.} } @article {Veerakumar2018207, title = {Ultrathin 2D graphitic carbon nitride nanosheets decorated with silver nanoparticles for electrochemical sensing of quercetin}, journal = {Journal of Electroanalytical Chemistry}, volume = {826}, year = {2018}, note = {

cited By 0

}, pages = {207-216}, abstract = {

In this work, we describe a facile fabrication of silver nanoparticles decorated on porous ultrathin two dimensional (2D) graphitic carbon nitride nanosheets (AgNPs@g-CN) via chemical approach, which was characterized by various analytical techniques including cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry. As expected, the AgNPs@g-CN modified glassy carbon electrode (AgNPs@g-CN/GCE) exhibited remarkable electrocatalytic activity towards the detection of quercetin (QCR) with a wide linear range from 1.0 {\texttimes} 10-8 to 1.2 {\texttimes} 10-4 mol L-1 and a lower detection limit of 6.0 {\texttimes} 10-9 mol L-1. Besides, the amperometric results revealed that the peak current for QCR could not affect upon the sequential additions of electroactive interfering species such as metal ions (300 μM), biomolecules (100 μM), and other flavonoids (50 μM) indicating the selectivity of the proposed sensor. Moreover, the AgNPs@g-CN modified electrode displayed higher stability and reproducibility towards the detection of QCR. The AgNPs@g-CN/GCE could also be used to detect QCR in green apple (GA) samples with satisfactory recoveries for practical applications. The concepts behind the novel architecture to modify electrodes can be potentially harnessed in other electrochemical sensors and photocatalysis applications. {\textcopyright} 2018 Elsevier B.V.

}, keywords = {Carbon nitride, Catalysis, Chemical analysis, Chronoamperometry, Cyclic voltammetry, Differential pulse voltammetry, Electrocatalysis, Electrocatalytic activity, Electrochemical sensing, Electrochemical sensors, Flavonoids, Glass, Glass membrane electrodes, Glassy carbon electrodes, Graphitic carbon nitrides, Metal ions, Metal nanoparticles, METALS, Modified glassy carbon electrode, NANOSHEETS, Nitrides, Phenols, Quercetin, Silver nanoparticles, Two Dimensional (2 D)}, doi = {10.1016/j.jelechem.2018.08.031}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85052726018\&doi=10.1016\%2fj.jelechem.2018.08.031\&partnerID=40\&md5=702b005e84deea7b296ba15304b0d2b9}, author = {P. Veerakumar and Rajkumar, C. and Chen, S.-M. and Thirumalraj, B. and Lin, K.-C.} } @article {Chao2017, title = {3D Probed Lipid Dynamics in Small Unilamellar Vesicles}, journal = {Small}, volume = {13}, number = {13}, year = {2017}, note = {

cited By 2

}, abstract = {

Single-molecule fluorescence correlation spectroscopy overcomes the resolution barrier of optical microscopy (10≈{\textendash}20 nm) and is utilized to look into lipid dynamics in small unilamellar vesicles (SUVs; diameter \< 100 nm). The fluorescence trajectories of lipid-like tracer 1,1'-dioctadecyl-3,3,3',3'-tetramethylindodicarbocyanine (DiD) in the membrane bilayers are acquired at a single-molecule level. The autocorrelation analysis yields the kinetic information on lipid organization, oxygen transport, and lateral diffusion in SUVs{\textquoteright} membrane. First, the isomerization feasibility may be restricted by the addition of cholesterols, which form structure conjugation with DiD chromophore. Second, the oxygen transport is prevented from the ultrasmall cluster and cholesterol-rich regions, whereas it can pass through the membrane region with liquid-disordered phase (Ld) and defects. Third, by analyzing 2D spectra correlating the lipid diffusion coefficient and triplet-state lifetime, the heterogeneity in lipid bilayer can be precisely visualized such as lipid domain with different phases, the defects of lipid packing, and DiD-induced {\textquotedblleft}bouquet{\textquotedblright} ultrasmall clusters. {\textcopyright} 2017 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim

}, keywords = {Autocorrelation analysis, Cholesterol, chromophores, DEFECTS, DYNAMICS, Fluorescence, Fluorescence spectroscopy, Kinetic information, Lipid bilayers, Lipid dynamics, MOLECULES, Optical correlation, Single molecule fluorescence, Single molecule level, Small unilamellar vesicle, Spectroscopic analysis, Synchrotrons, Triplet state lifetime, Unilamellar vesicle}, doi = {10.1002/smll.201603408}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85017105024\&doi=10.1002\%2fsmll.201603408\&partnerID=40\&md5=ae4b458e0331d91b36bb62a309b8af6b}, author = {Chao, M.-H. and Lin, Y.-T. and Dhenadhayalan, N. and Lee, H.-L. and H.-Y. Lee and Lin, K.-C.} } @conference {Lin2017, title = {Angular distribution of bromine atomic photofragment in oriented 2-bromobutane via hexapole state selector}, booktitle = {AIP Conference Proceedings}, volume = {1906}, year = {2017}, note = {

cited By 0

}, abstract = {

In this work, an asymmetric top molecule 2-bromobutane has been successfully oriented by using hexapole state selector combined with orientation field, followed by detection of the bromine atomic photofragment distribution in the photolysis. The photofragment is produced in both the ground Br (2P3/2) and the excited Br (2P1/2) electronic states and both channels are studied by the slice imaging technique, revealing new features in the stereodynamic vectorial properties with respect to previous investigations on non-oriented molecules. {\textcopyright} 2017 Author(s).

}, doi = {10.1063/1.5012287}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85038856547\&doi=10.1063\%2f1.5012287\&partnerID=40\&md5=51a90b9840d074f07fa95411a8f7f5bf}, author = {Lin, K.-C. and Nakamura, M. and Yang, S., Jr. and Kasai, T. and Che, D.-C. and Lombardi, A. and Palazzetti, F. and Aquilanti, V.} } @article {Veerakumar20175302, title = {Biomass Derived Sheet-like Carbon/Palladium Nanocomposite: An Excellent Opportunity for Reduction of Toxic Hexavalent Chromium}, journal = {ACS Sustainable Chemistry and Engineering}, volume = {5}, number = {6}, year = {2017}, note = {

cited By 10

}, pages = {5302-5312}, abstract = {

Palladium nanoparticles (Pd NPs) immobilized on a garlic skin-derived activated carbons (GACs) is reported. The morphology, structure, surface compositions, and textural properties of the GACs and Pd@GAC catalyst were investigated by a variety of physicochemical characterization techniques, which revealed a dispersion of Pd NPs with average particle size of ca. 21 nm on sheet-like graphitized GACs with surface areas and pore volumes as high as 1836 m2 g-1 and 0.89 cm3 g-1, respectively. As a result, the Pd@GAC with a Pd loading of ca. 1-2 wt\% exhibited superior activity for catalytic reduction of toxic Cr(VI) to Cr(III) surpassing most metal-based catalysts reported in the literature. As evidenced by a comprehensive UV-vis spectrophotometric study, the eco-friendly Pd@GAC catalyst reported herein, which can be facilely prepared with biowaste feedstocks, also showed excellent catalytic performances for efficient reduction of Cr(VI) with extraordinary stability and recyclability over at least five repeated catalytic test cycles. {\textcopyright} 2017 American Chemical Society.

}, keywords = {Activated carbon, Average particle size, Catalyst activity, Catalysts, Catalytic performance, Catalytic reduction, Chromium, Chromium compounds, Formic acid, Granular materials, Metal-based catalysts, NANOPARTICLES, palladium, Palladium nanoparticles, particle size, Physico-chemical characterization, Spectrophotometric study, Textural properties}, doi = {10.1021/acssuschemeng.7b00645}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85020172573\&doi=10.1021\%2facssuschemeng.7b00645\&partnerID=40\&md5=a0f63c8378c79e8aca8f3769eb8533c7}, author = {P. Veerakumar and Thanasekaran, P. and Lin, K.-C. and Liu, S.-B.} } @article {Huang20172888, title = {Cl2 Elimination in 248 nm Photolysis of (COCl)2 Probed with Cavity Ring-Down Absorption Spectroscopy}, journal = {Journal of Physical Chemistry A}, volume = {121}, number = {15}, year = {2017}, note = {

cited By 1

}, pages = {2888-2895}, abstract = {

Cavity ring-down absorption spectroscopy (CRDS) is employed to investigate one-photon dissociation of (COCl)2 at 248 nm obtaining a primary Cl2 elimination channel. A ratio of vibrational population is estimated to be 1:(0.12 {\textpm} 0.03):(0.011 {\textpm} 0.003) for the v = 0, 1, and 2 levels. The quantum yield of Cl2 molecular channel is obtained to be 0.8 {\textpm} 0.4 initiated from the X̃ 1Ag ground state surface (COCl)2 via internal conversion. The obtained total quantum yield is attributed to both primary ((COCl)2 + hν {\textrightarrow} 2CO + Cl2) and secondary reactions (dominated by Cl + COCl {\textrightarrow} Cl2 + CO). The former is estimated to share a yield of \>0.14, while the latter contributes up to 0.66. The photodissociation pathway to the molecular products is calculated to proceed via a four-center transition state (TS) from which Cl2 is eliminated synchronously. Installation of the mirrors with reflectivity of 99.995\% in the CRDS apparatus prolongs the ring-down time to 70 μs, thus allowing for the contribution from 17\% up to 66\% of the total Cl2 yield from secondary reaction depending on the reaction temperature. Despite uncertainty in determining the product yield, the primary Cl2 dissociation channel eliminated from (COCl)2 is observed for the first time. {\textcopyright} 2017 American Chemical Society.

}, keywords = {Absorption spectroscopy, DISSOCIATION, Dissociation channels, Ground state, Ground-state surface, Internal conversions, Light measurement, Molecular channels, Photodissociation, Photolysis, quantum theory, Quantum yield, Reaction temperature, Secondary reactions, Transition state, Vibrational population}, doi = {10.1021/acs.jpca.6b12810}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85020055777\&doi=10.1021\%2facs.jpca.6b12810\&partnerID=40\&md5=32af45031b46be135c0ea3bc09325c32}, author = {Huang, T.-K. and Chen, B.-J. and Lin, K.-C. and Lin, L. and Sun, B.-J. and A.H.H. Chang} } @article {Veerakumar20178475, title = {Computational Studies of Versatile Heterogeneous Palladium-Catalyzed Suzuki, Heck, and Sonogashira Coupling Reactions}, journal = {ACS Sustainable Chemistry and Engineering}, volume = {5}, number = {10}, year = {2017}, note = {

cited By 5

}, pages = {8475-8490}, abstract = {

This perspective focuses on the mechanistic insights and complexity, which are difficult to acquire from pure experimental techniques, of the computational studies of Pd-catalyzed Suzuki, Heck, and Sonogashira carbon-carbon bond-forming reactions. These reactions consist of three fundamental steps including oxidative addition (OA), transmetalation (TM), and reductive elimination (RE) for the generation of carbon-carbon bonds from the bond-forming reactions of aryl halides (R1X) and organometallic species (R2M). Computational studies of these coupling reactions allow us to understand specific reaction pathways in the analysis of OA (resolving the linkage between coordination number and selectivity in Suzuki reaction), TM (the function of the base in the Suzuki reaction and various mechanistic options in the Sonogashira reaction), and RE (way of efficient β-hydride elimination in the Heck reaction). In addition, the reaction pathways and complexities in the full catalytic cycle of each reaction along with the future perspective are also discussed. {\textcopyright} 2017 American Chemical Society.

}, keywords = {C-C cross-couplings, Catalysis, Chemical bonds, Chemical reactions, Coordination reactions, Covalent bonds, Density functional theory, Heck reactions, Heterogeneous, Mechanisms, Organometallics, palladium, Sonogashira reactions, Suzuki reaction}, doi = {10.1021/acssuschemeng.7b00922}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85030471154\&doi=10.1021\%2facssuschemeng.7b00922\&partnerID=40\&md5=e3f689900976928fcf093257d4893950}, author = {P. Veerakumar and Thanasekaran, P. and Lu, K.-L. and Lin, K.-C. and Rajagopal, S.} } @article {Kasai201725, title = {Coordinate Analysis for Interpreting the Decoherence in the Coherent NO with Ar Collision: A Physico-mathematical Picture Using the Stereographic Projection and the Cusp Catastrophe}, journal = {Journal of the Chinese Chemical Society}, volume = {64}, number = {1}, year = {2017}, note = {

cited By 2

}, pages = {25-35}, abstract = {

We present here a physico-mathematical picture for explaining the unexpectedly large decoherence cross-section (almost 10 times larger than its gas-kinematic cross-section) recently observed by Ure{\~n}a and coworkers in their scattering experiment involving a coherent NO beam with Ar gas. The present topological picture consists of a stereographic projection and the cusp catastrophe theory of Thom, and we find that this model enables us to clarify the origin of the collisional decoherence. From the view of the stereographic projection, we can naturally introduce the wave property originating from the singular point at the {\textquotedblleft}North pole{\textquotedblright} on the circumference S1 coordinate corresponding to a critical point for the collisional decoherence (condition 1). This picture also predicts the sudden changes of wave-phase collapse due to network interaction in the many-body system (condition 2). Thus it is hoped that the model proposed by Ure{\~n}a et al. based on the dipole-induced dipole interaction in the NO + Ar system could be modified through this picture by including interactions with many Ar atoms in the environment. One way to fill the gap between the single-pair interaction picture and the multiple interaction one would be to employ theoretical calculations by use of the density matrix theory with and without adding the second Ar atom to the NO{\textendash}Ar system. The cusp catastrophe theory reinforces the necessity of some cooperative network interaction between the coherent NO molecule and many neighboring Ar atoms and provides a qualitative scenario in which the whole system leads to a sudden change of the collisional decoherence of NO as a function of the control parameters (a, b). At this stage, the present physico-mathematical picture cannot give any specific values of the decoherence distance by the theory itself, but it clearly provides us a new topological concept for clarifying the origin of collisional decoherence which is strongly connected with the complexity of the system. Thus it gives us a global guide map toward further clarification of the collisional decoherence phenomenon with the aid of more sophisticated quantum mechanical calculations in the future. {\textcopyright} 2016 The Chemical Society Located in Taipei \& Wiley-VCH Verlag GmbH \& Co. KGaA, Weinheim

}, doi = {10.1002/jccs.201600290}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85006142766\&doi=10.1002\%2fjccs.201600290\&partnerID=40\&md5=73d96485a0b5afe37de7e69c701120cf}, author = {Kasai, T. and Lin, K.-C.} } @article {Veerakumar20173598, title = {Graphene Oxide Nanosheets as An Efficient and Reusable Sorbents for Eosin Yellow Dye Removal from Aqueous Solutions}, journal = {ChemistrySelect}, volume = {2}, number = {13}, year = {2017}, note = {

cited By 8

}, pages = {3598-3607}, abstract = {

In this study, 2D graphene oxide nanosheets (GONS) were synthesized and characterized by XRD, Raman, SEM, FE-SEM, TEM, XPS, TGA, UV-vis and FTIR spectral techniques. The efficiency of eosin yellow (EY) dye adsorption on the GONS under various experimental parameters such as contact time, pH and temperature was investigated. Adsorption kinetic data were characterized appropriately using pseudo second-order-kinetics and intraparticle diffusion methods. Free energy of adsorption (ΔG0), enthalpy (ΔH0), entropy (ΔS0) changes, activation energy and Arrhenius factors were also calculated. The endothermic and spontaneous nature of the adsorption process was confirmed by the positive value of the enthalpy change (ΔH0) and the negative value of free energy change (ΔG0). The adsorption mechanism was investigated by FTIR spectra of GONS before and after adsorption of EY dye molecules. The remarkable adsorption capacity of EY onto the GONS can be attributed to the various adsorption interaction mechanisms such as hydrogen bonding, π-π electron, and electrostatic interactions. The maximum adsorption capacity for EY was calculated to be 217.33 mg g-1. {\textcopyright} 2017 Wiley-VCH Verlag GmbH \& Co. KGaA, Weinheim

}, doi = {10.1002/slct.201700281}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85041547840\&doi=10.1002\%2fslct.201700281\&partnerID=40\&md5=f0683d2cac158b0a762c3744ea51a07d}, author = {P. Veerakumar and Tharini, J. and Ramakrishnan, M. and Panneer Muthuselvam, I. and Lin, K.-C.} } @conference {Kasai2017, title = {Role of cooperative network interaction in transition region of roaming reactions: Non-equilibrium steady state vs. thermal equilibrium reaction scheme}, booktitle = {AIP Conference Proceedings}, volume = {1906}, year = {2017}, note = {

cited By 1

}, abstract = {

This paper proposes a new type of roaming mechanism. We find a signature of trajectory with chaotic behavior in the action-angle diagram of the H + H2 reaction on a LEP surface, namely the trajectory is found to be very sensitive to the initial angle variable which corresponds to the phase of the H2 vibration. The trajectory pattern switches from the direct to the complex forming mechanism, and vice versa, in the angle range (0 \~{} π). In the complex forming angle range, trajectories switch from reactive to non-reactive randomly and suddenly, as the result, we cannot predict the collision pattern from the initial conditions. Therefore, we may classify such trajectory as a new type of roaming with chaotic behavior, and it is different from the ordinary trajectory with deterministic behavior. This chaotic behavior could be due cooperative nearby network interaction (CNN effect). We also suggest that the KPP (Kolmogorow-Petrovsky-Piskounov) equation is useful to estimate the density gradient of the activated reagents, so that one can evaluate the branching ratio to various exit channels, such as triple fragmentation, tight transition state, or the roaming channel with the aid of the present classical trajectory calculation. {\textcopyright} 2017 Author(s).

}, doi = {10.1063/1.5012288}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85038816707\&doi=10.1063\%2f1.5012288\&partnerID=40\&md5=24c49a4b6a4083b13a6c0ca324c4e8fd}, author = {Kasai, T. and Muthiah, B. and Lin, K.-C.} } @article {Veerakumar20171398, title = {Silver Nanoparticles Modified Graphitic Carbon Nitride Nanosheets as a Significant Bifunctional Material for Practical Applications}, journal = {ChemistrySelect}, volume = {2}, number = {4}, year = {2017}, note = {

cited By 3

}, pages = {1398-1408}, abstract = {

Amine-functionalized graphitic carbon nitride (NH2/GCN) nanosheets photoluminescence, catalytic properties and excellent water dispersion stability were prepared and characterized by a variety of different analytical and spectroscopic techniques. The well-dispersed NH2/GCN nanosheets were found to exhibit remarkable pH sensing sensitivity at an ambient temperature with desirable broad detection range (1 <= pH <= 12). Moreover, upon incorporating silver nanoparticles (Ag NPs), the Ag-NH2/GCN nanocomposites showed excellent performances for catalytic reduction of 4-nitrophenol (4-NP) in NaBH4 with a superior rate constant (k) of 0.1594 s-1 within as short as 30 s. The NH2/GCN and Ag-NH2/GCN nanocomposites reported herein therefore render prospective applications as sensitive pH and practical catalytic applications. {\textcopyright} 2017 Wiley-VCH Verlag GmbH \& Co. KGaA, Weinheim

}, doi = {10.1002/slct.201601919}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85041497096\&doi=10.1002\%2fslct.201601919\&partnerID=40\&md5=3d67ad81d8b77fe434361d566581e298}, author = {P. Veerakumar and Dhenadhayalan, N. and Lin, K.-C. and Liu, S.-B.} } @article {Nakamura2017, title = {Stereodirectional images of molecules oriented by a variable-voltage hexapolar field: Fragmentation channels of 2-bromobutane electronically excited at two photolysis wavelengths}, journal = {Journal of Chemical Physics}, volume = {147}, number = {1}, year = {2017}, note = {

cited By 7

}, abstract = {

The asymmetric-top molecule 2-bromobutane is oriented by means of a hexapole state selector; the angular distribution of the bromine atom photofragment, for the two fine-structure components, is acquired by velocity-map ion imaging. The molecular beam, spatially oriented along the time-of-flight axis, is intersected with a linearly polarized laser, whose polarization is tilted by 45{\textdegree} with respect to the detector surface. To obtain the mixing ratio of the perpendicular and parallel transitions, the fragment ion images and angular distributions can be appropriately simulated to give insight on the population mechanism of the specific electronic state involved at each selected excitation wavelength. The photofragment images obtained at 238.6 nm yielded an asymmetry factor β1 of 0.67, indicative of the extent of molecular orientation, and an anisotropy parameter β2 of 1.03, which is a signature of a prevailing parallel transition along the C-Br axis. When the photolysis wavelength is tuned to 254.1 nm, the corresponding angular distribution is less asymmetric (β1 = 0.24) and the obtained small value β2 = 0.12 is a characteristic of a predominantly perpendicular transition. The photofragment angular distributions are also affected by hexapole voltage, especially regarding the asymmetry factor, and this aspect provides information on the effect of molecular orientation. {\textcopyright} 2017 Author(s).

}, keywords = {Angular distribution, Anisotropy parameters, Detector surfaces, Excitation wavelength, Excited states, Fragmentation channels, Linearly polarized lasers, Molecular beams, Molecular orientation, MOLECULES, Parallel transitions, Photolysis, Photolysis wavelength, Polarization, Velocity map ion imaging}, doi = {10.1063/1.4981025}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85018505764\&doi=10.1063\%2f1.4981025\&partnerID=40\&md5=14c4f37f8e82f12ddbd3ff171159f8aa}, author = {Nakamura, M. and Yang, S., Jr. and Lin, K.-C. and Kasai, T. and Che, D.-C. and Lombardi, A. and Palazzetti, F. and Aquilanti, V.} } @article {Wu201734, title = {Two-color resonant two-photon ionization and mass-analyzed threshold ionization spectroscopy of 4-chlorostyrene}, journal = {Chemical Physics Letters}, volume = {682}, year = {2017}, note = {

cited By 3

}, pages = {34-37}, abstract = {

The first electronic excitation and adiabatic ionization energies of 35Cl and 37Cl 4-chlorostyrene were similar, with values of 33,977~{\textpm}~2 and 67,972~{\textpm}~5~cm-1, respectively. The general features in the obtained vibronic and cation spectra of the two isotopologues were similar. A frequency shift of 1{\textendash}5~cm-1 was observed on many active vibrations of the 35Cl and 37Cl isotopologues of 4-chlorostyrene in the S1 and D0 states. This frequency difference at each mode may reflect the degree of Cl atom involvement in the overall vibration. {\textcopyright} 2017 Elsevier B.V.

}, keywords = {4-Chlorostyrene, Ionization, Isomers, Isotopologues, Mass analyzed threshold ionization, Photoionization, Photons, Positive ions, Two photon ionization, Vibronic spectra}, doi = {10.1016/j.cplett.2017.05.058}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85020255182\&doi=10.1016\%2fj.cplett.2017.05.058\&partnerID=40\&md5=bb5387360c424f0758654f60d1526650}, author = {Wu, P.Y. and Huang, H.H. and K.C. Lin and Tzeng, W.B.} } @article {Dhenadhayalan201712087, title = {Ultra-sensitive DNA sensing of a prostate-specific antigen based on 2D nanosheets in live cells}, journal = {Nanoscale}, volume = {9}, number = {33}, year = {2017}, note = {

cited By 4

}, pages = {12087-12095}, abstract = {

Herein, we report ultra-sensitive sensing of a prostate-specific antigen (PSA), which is used as a biomarker to detect prostate cancer, using a molybdenum series (MoO3, MoS2, and MoSe2) of two-dimensional nanosheets (2D NSs). Moreover, the design of a 2D NS-based PSA aptamer sensor system was demonstrated based on a fluorescence turn-on mechanism in the presence of a target. The 2D NSs acted as an excellent sensing platform in which the PSA aptamer was adsorbed on the NSs and subsequent energy transfer between them led to fluorescence quenching of the aptamer. The detection limit of PSA was achieved to be 13 pM for MoO3 NSs, whereas the MoS2 and MoSe2 systems exhibited a detection limit of 72 and 157 pM, respectively. To the best of our knowledge, this is the first report on the ultra-sensitive detection of a 2D NS-based aptamer sensor. The in vitro bioimaging measurements were performed using confocal fluorescence microscopy. Herein, PSA detection was successfully demonstrated in human embryonic kidney 293T (HEK) live cells. Moreover, the MoO3, MoS2, and MoSe2 NSs exhibit excellent biocompatibility and low toxicity; thus, these 2D NSs can be used as a promising sensor platform to detect prostate cancer. This journal is {\textcopyright} The Royal Society of Chemistry.

}, keywords = {Antigens, Biocompatibility, Biosensing Techniques, Chemistry, Confocal, Confocal fluorescence microscopy, confocal microscopy, Detection limits, Diseases, DNA, Energy transfer, Fluorescence, Fluorescence microscopy, Fluorescence quenching, genetic procedures, HEK293 cell line, HEK293 Cells, human, Human embryonic kidneys, Humans, limit of detection, male, MICROSCOPY, molybdenum, Molybdenum oxide, nanomaterial, NANOSHEETS, NANOSTRUCTURES, Prostate cancers, Prostate specific antigen, prostate tumor, Prostate-Specific Antigen, Prostatic Neoplasms, Quenching, Sensing platforms, Two dimensional nanosheets, Urology}, doi = {10.1039/c7nr03431h}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85028440294\&doi=10.1039\%2fc7nr03431h\&partnerID=40\&md5=eb3233a26be749539cc67e16a9e1aa54}, author = {Dhenadhayalan, N. and K. Yadav and Sriram, M.I. and Lee, H.-L. and Lin, K.-C.} } @article {Veerakumar2017271, title = {Well-dispersed rhenium nanoparticles on three-dimensional carbon nanostructures: Efficient catalysts for the reduction of aromatic nitro compounds}, journal = {Journal of Colloid and Interface Science}, volume = {506}, year = {2017}, note = {

cited By 5

}, pages = {271-282}, abstract = {

Rhenium nanoparticles (ReNPs) supported on ordered mesoporous carbon (OMC) as a catalyst (Re/OMC) through a solvent-evaporation induced self-assembly (ELSA) method were prepared. The synthesized heterogonous catalyst was fully characterized using X-ray diffraction, field emission transmission electron microscopy, N2 sorption, metal dispersion, thermogravimetric analysis, Raman, Fourier-transform infrared, and X-ray photon spectroscopies. In addition, the catalyst was applied to reduce the aromatic nitro compounds (ANCs) for the first time in aqueous media and the reactions were monitored by following the intensity changes in the UV{\textendash}vis absorption spectra with respect to time. This method provides the advantages of obtaining a high rate constant (k), green reaction conditions, simple methodology, easy separation and easy workup procedures. Moreover, the catalyst can be easily recovered by centrifugation, recycled several times and reused without any loss of activity. The higher activity of this catalyst was attributed to higher dispersion and smaller particle size of ReNPs as observed from FE-TEM and XRD results. {\textcopyright} 2017

}, keywords = {2, 2 nitroaniline, 4 dinitrophenol, 4 nitroaniline, 4 nitrophenol, Absorption spectroscopy, aniline derivative, Aromatic compounds, aromatic nitro compound, Aromatic nitro compounds, Article, atomic emission spectrometry, carbon nanoparticle, catalyst, Catalyst activity, Catalysts, Catalytic reduction, copper, DISPERSION, electron transport, Elemental analysis, energy dispersive X ray spectroscopy, field emission transmission electron microscopy, Field-emission transmission electron microscopies, Fourier transform infra reds, gasification, High resolution transmission electron microscopy, hydrogenation, inductively coupled plasma atomic emission spectroscopy, infrared spectroscopy, microwave irradiation, nanoparticle, NANOPARTICLES, NANOSTRUCTURES, nitrobenzene, Ordered mesoporous carbon, particle size, picric acid, priority journal, Raman spectrometry, Rate constants, reduction (chemistry), Rhenium, Sodium boro hydrides, surface property, Thermogravimetric analysis, thermogravimetry, Toxic pollutants, Transmission electron microscopy, ultraviolet spectrophotometry, unclassified drug, X ray diffraction, X ray photoelectron spectroscopy, X ray photon spectroscopy}, doi = {10.1016/j.jcis.2017.07.065}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85025102865\&doi=10.1016\%2fj.jcis.2017.07.065\&partnerID=40\&md5=1fa09eb1a24ce347b1f00f1deab83fb9}, author = {P. Veerakumar and Thanasekaran, P. and Lin, K.-C. and Liu, S.-B.} } @article {Veerakumar20166772, title = {Biomass-Derived Activated Carbon Supported Fe3O4 Nanoparticles as Recyclable Catalysts for Reduction of Nitroarenes}, journal = {ACS Sustainable Chemistry and Engineering}, volume = {4}, number = {12}, year = {2016}, note = {

cited By 19

}, pages = {6772-6782}, abstract = {

Highly porous beetroot-derived activated carbons incorporated with well-dispered magnetite nanoparticles (Fe3O4 NPs; average size ca. 3.8 {\textpm} 0.5 nm) were fabricated via a microwave-assisted synthesis route. The magnetic Fe3O4@BRAC catalysts so-fabricated were characterized by a variety of diffent physicochemical teniques, viz. XRD, FE-TEM, VSM, gas physisorption/chemisorption, TGA, XPS, Raman, ICP-AES, and FT-IR spectroscopy. The as-prepared catalysts were exploited for heterogeneous-phase reduction of a series of nitroaromatics (RNO2; R = H, OH, NH2, CH3, and COOH) under KOH as a base, isopropyl alcohol acting as a hydrogen donor as well as solvent and also tested with other solvents. The reaction system not only exhibits excellent activity with high anilines yield but also represents a green and durable catalytic process, which facilitates facile operation, easy separation, and catalyst recycle. {\textcopyright} 2016 American Chemical Society.

}, keywords = {Activated carbon, Activated carbon supported, Atomic emission spectroscopy, Catalysis, Catalysts, Heterogeneous phase, Isopropyl alcohols, Magnetite nanoparticles, Microwave assisted synthesis, NANOPARTICLES, Nitro-aromatics, Porous carbons, Porous materials, Recyclable catalyst, Reduction of nitroarenes}, doi = {10.1021/acssuschemeng.6b01727}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85002323064\&doi=10.1021\%2facssuschemeng.6b01727\&partnerID=40\&md5=c98d1fda7d7194d7fc5fa8887c9baab9}, author = {P. Veerakumar and Panneer Muthuselvam, I. and Hung, C.-T. and Lin, K.-C. and Chou, F. -C. and Liu, S.-B.} } @article {Nakamura20165389, title = {Hexapole-Oriented Asymmetric-Top Molecules and Their Stereodirectional Photodissociation Dynamics}, journal = {Journal of Physical Chemistry A}, volume = {120}, number = {27}, year = {2016}, note = {

cited By 11

}, pages = {5389-5398}, abstract = {

Molecular orientation is a fundamental requisite in the study of stereodirected dynamics of collisional and photoinitiated processes. In this past decade, variable hexapolar electric filters have been developed and employed for the rotational-state selection and the alignment of molecules of increasing complexity, for which the main difficulties are their mass, their low symmetry, and the very dense rotational manifold. In this work, for the first time, a complex molecule such as 2-bromobutane, an asymmetric top containing a heavy atom (the bromine), was successfully oriented by a weak homogeneous field placed downstream from the hexapolar filter. Efficiency of the orientation was characterized experimentally, by combining time-of-flight measurements and a slice-ion-imaging detection technique. The application is described to the photodissociation dynamics of the oriented 2-bromobutane, which was carried out at a laser wavelength of 234 nm, corresponding to the breaking of the C-Br bond. The Br photofragment is produced in both the ground Br (2P3/2) and the excited Br (2P1/2) electronic states, and both channels are studied by the slice imaging technique, revealing new features in the velocity and angular distributions with respect to previous investigations on nonoriented molecules. {\textcopyright} 2016 American Chemical Society.

}, keywords = {Asymmetric top, Chemical reactions, Complex molecules, DYNAMICS, Homogeneous field, Imaging techniques, Laser wavelength, Molecular orientation, MOLECULES, Photodissociation, Photodissociation dynamics, Photofragments, Rotational state, Time of flight measurements}, doi = {10.1021/acs.jpca.6b02410}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84978719232\&doi=10.1021\%2facs.jpca.6b02410\&partnerID=40\&md5=e9f15294ac85a7040280995fd45132d5}, author = {Nakamura, M. and Yang, S.-J. and Tsai, P.-Y. and Kasai, T. and Lin, K.-C. and Che, D.-C. and Lombardi, A. and Palazzetti, F. and Aquilanti, V.} } @article {Lin20166980, title = {Regulation of nonadiabatic processes in the photolysis of some carbonyl compounds}, journal = {Physical Chemistry Chemical Physics}, volume = {18}, number = {10}, year = {2016}, note = {

cited By 5

}, pages = {6980-6995}, abstract = {

Carbonyl compounds studied are confined to acetyl halide (CH3COCl), acetyl cyanide (CH3COCN), acetyl sulfide (CH3COSH), acetaldehyde (CH3CHO), and methyl formate (HCOOCH3). They are asymmetrically substituted, but do not follow the well-known Norrish type I reactions. Each compound ejected in an effusive beam at about 300 K is commonly excited to the 1(n, π*)CO lower state; that is, a nonbonding electron on O of the C=O group is promoted to the antibonding orbital of π*CO. The photolysis experiments are conducted in the presence of Ar gas and the corresponding fragments are detected using time-resolved Fourier-transform Infrared (FTIR) emission spectroscopy. The enhancement of the collision-induced internal conversion or intersystem crossing facilitates the dissociation channels via highly vibrational states of the ground singlet (So) or triplet (T1) potential energy surfaces. In this manner, an alternative nonadiabatic channel is likely to open yielding different products, even if the diabatic coupling strength is strong between the excited state and the neighboring state. For instance, the photodissociation of CH3COCl at 248 nm produces HCl, CO, and CH2 fragments, in contrast to the supersonic jet experiments showing dominance of the Cl fragment eliminated from the excited state. If the diabatic coupling strength is weak, dissociation proceeds mainly through internal conversion, such as the cases of CH3COCN and CH3COSH. The photodissociation of CH3COCN at 308 nm has never been reported before, while for CH3COSH matrix-isolated photodissociation was conducted that shows a distinct spectral feature from the current FTIR method. The CH3CHO and HCOOCH3 molecules belong to the same type of carbonyl compounds, in which the molecular products, CO + CH4 and CO + CH3OH, are produced through both transition state and roaming pathways. Their products are characterized differently between molecular beam and current FTIR experiments. For instance, the photodissociation of HCOOCH3 at 248 nm yields CO with the vibrational state v >= 4, in contrast to the molecular beam experiments producing CO at v = 1. The photodissociation of CH3CHO at 308 nm intensifies a low energy component in the CH4 vibrational distribution, thus verifying the transition state pathway for the first time. {\textcopyright} the Owner Societies 2016.

}, doi = {10.1039/c5cp07012k}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84960193879\&doi=10.1039\%2fc5cp07012k\&partnerID=40\&md5=92ce48f894683f24607fc657a303d9b7}, author = {Lin, K.-C.} } @conference {Palazzetti2016, title = {Rotational state-selection and alignment of chiral molecules by electrostatic hexapoles}, booktitle = {AIP Conference Proceedings}, volume = {1790}, year = {2016}, note = {

cited By 1

}, abstract = {

Electrostatic hexapoles are revealed as a powerful tool in the rotational state-selection and alignment of molecules to be utilized in beam experiments on collisional and photoinitiated processes. In the paper, we report results on the application of the hexapolar technique on the recently studied chiral molecules propylene oxide, 2-butanol and 2-bromobutane, to be investigated in selective photodissociation and enantiomeric discrimination. {\textcopyright} 2016 Author(s).

}, doi = {10.1063/1.4968645}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85008674865\&doi=10.1063\%2f1.4968645\&partnerID=40\&md5=9dd2dc63cf1625b4c3c06d9f68a24795}, author = {Palazzetti, F. and Lombardi, A. and Nakamura, M. and Yang, S.-J. and Kasai, T. and Lin, K.-C. and Tsai, P.-Y. and Che, D.-C.} } @article {Dhenadhayalan201623953, title = {Silicon Quantum Dot-Based Fluorescence Turn-On Metal Ion Sensors in Live Cells}, journal = {ACS Applied Materials and Interfaces}, volume = {8}, number = {36}, year = {2016}, note = {

cited By 10

}, pages = {23953-23962}, abstract = {

Multiple sensor systems are designed by varying aza-crown ether moiety in silicon quantum dots (SiQDs) for detecting individual Mg2+, Ca2+, and Mn2+ metal ions with significant selectivity and sensitivity. The detection limit of Mg2+, Ca2+, and Mn2+ can reach 1.81, 3.15, and 0.47 μM, respectively. Upon excitation of the SiQDs which are coordinated with aza-crown ethers, the photoinduced electron transfer (PET) takes place from aza-crown ether moiety to the valence band of SiQDs core such that the reduced probability of electron-hole recombination may diminish the subsequent fluorescence. The fluorescence suppression caused by such PET effect will be relieved after selective metal ion is added. The charge-electron binding force between the metal ion and aza-crown ether hinders the PET and thereby restores the fluorescence of SiQDs. The design of sensor system is based on the fluorescence "turn-on" of SiQDs while in search of the appropriate metal ion. For practical application, the sensing capabilities of metal ions in the live cells are performed and the confocal image results reveal their promising applicability as an effective and nontoxic metal ion sensor. {\textcopyright} 2016 American Chemical Society.

}, keywords = {Aza-crown-ether, Bio-imaging, Calcium, cell survival, crown ether, Crown ethers, Electron transitions, Electron-hole recombination, ELECTRONS, Ethers, Fluorescence, Fluorescence suppression, ion, Ions, Ligands, Manganese, METAL, Metal ions, METALS, Multiple sensor systems, Nanocrystals, Negative ions, Photo-induced electron transfer, quantum dot, quantum dots, Selectivity and sensitivity, Semiconductor quantum dots, Sensors, Silicon, Silicon quantum dots}, doi = {10.1021/acsami.6b07789}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84987738953\&doi=10.1021\%2facsami.6b07789\&partnerID=40\&md5=102427c9edc5b378a63d40986eadd06a}, author = {Dhenadhayalan, N. and Lee, H.-L. and K. Yadav and Lin, K.-C. and Lin, Y.-T. and A.H.H. Chang} } @conference {Palazzetti2016, title = {Stereodirectional photodynamics: Experimental and theoretical perspectives}, booktitle = {AIP Conference Proceedings}, volume = {1790}, year = {2016}, note = {

cited By 2

}, abstract = {

Hexapole oriented 2-bromobutane is photodissociated and detected by a slice-ion-imaging technique at 234 nm. The laser wavelength corresponds to the C - Br bond breaking with emission of a Br atom fragment in two accessible fine-structure states: the ground state Br (2P3/2) and the excited state Br (2P1/2), both observable separately by resonance-enhanced multiphoton ionization (REMPI). Orientation is evaluated by time-of-flight measurements combined with slice-ion-imaging. {\textcopyright} 2016 Author(s).

}, doi = {10.1063/1.4968646}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85008700667\&doi=10.1063\%2f1.4968646\&partnerID=40\&md5=f8537415901c6cd19a12b4dad65649fa}, author = {Palazzetti, F. and Lombardi, A. and Yang, S.-J. and Nakamura, M. and Kasai, T. and Lin, K.-C. and Che, D.-C. and Tsai, P.-Y.} } @article {Dhenadhayalan20161252, title = {Unravelling the Multiple Emissive States in Citric-Acid-Derived Carbon Dots}, journal = {Journal of Physical Chemistry C}, volume = {120}, number = {2}, year = {2016}, note = {

cited By 78

}, pages = {1252-1261}, abstract = {

Steady-state and time-resolved fluorescence spectroscopy techniques were used to probe multifluorescence resulting from citric-acid-derived carbon dots (C-dots). Commonly, both carboxyl-/amine-functionalized C-dots exhibit three distinct emissive states corresponding to the carbon-core and surface domain. The shorter-wavelength fluorescence (below 400 nm) originates from the carbon-core absorption band at \~{}290 nm, whereas the fluorescence (above 400 nm) is caused by two surface states at \~{}350 and 385 nm. In addition to three emissive states, a molecular state was also found in amine-functionalized C-dots. Time-resolved emission spectra (TRES) and time-resolved area normalized emission spectra (TRANES) were analyzed to confirm the origin of excitation wavelength-dependent fluorescence of C-dots. The surface functional groups on the C-dots are capable of regulating the electron transfer to affect the multifluorescence behavior. The electron transfer takes place from the carbon-core to surface domain by the presence of -COOH on the surface and vice versa for the case of -NH2 present on the surface. To the best of our knowledge, this is the first report that the multiemissive states are probed in C-dots systems using TRES and TRANES analyses, and related fluorescence mechanisms are verified clearly. {\textcopyright} 2015 American Chemical Society.

}, keywords = {Citric acid, Electron transfer, Electron transitions, Emission spectroscopy, Emission spectrums, Excitation wavelength, Fluorescence, Fluorescence spectroscopy, Shorter wavelength, Surface domains, Surface functional groups, Time-resolved emission spectra, Time-resolved fluorescence spectroscopy}, doi = {10.1021/acs.jpcc.5b08516}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84955516013\&doi=10.1021\%2facs.jpcc.5b08516\&partnerID=40\&md5=0421e5d1020ec6d0e669d6cb6760a6f6}, author = {Dhenadhayalan, N. and Lin, K.-C. and Suresh, R. and Ramamurthy, P.} } @article {Chen20157838, title = {Characterization of molecular channel in photodissociation of SOCl2 at 248 nm: Cl2 probing by cavity ring-down absorption spectroscopy}, journal = {Physical Chemistry Chemical Physics}, volume = {17}, number = {12}, year = {2015}, note = {

cited By 3

}, pages = {7838-7847}, abstract = {

A primary elimination channel of the chlorine molecule in the one-photon dissociation of SOCl2 at 248 nm was investigated using cavity ring-down absorption spectroscopy (CRDS). By means of spectral simulation, the ratio of the vibrational population in the v = 0, 1, and 2 levels was evaluated to be 1:(0.10 {\textpm} 0.02):(0.009 {\textpm} 0.005), corresponding to a Boltzmann vibrational temperature of 340 {\textpm} 30 K. The Cl2 molecular channel was obtained with a quantum yield of 0.4 {\textpm} 0.2 from the X1A' ground state of SOCl2via internal conversion. The dissociation mechanism differs from a prior study where a smaller yield of \<3\% was obtained, initiated from the 21A' excited state. Temperature-dependence measurements of the Cl2 fragment turn out to support our mechanism. With the aid of ab initio potential energy calculations, two dissociation routes to the molecular products were found, including one synchronous dissociation pathway via a three-center transition state (TS) and the other sequential dissociation pathway via a roaming-mediated isomerization TS. The latter mechanism with a lower energy barrier dominates the dissociation reaction. This journal is {\textcopyright} the Owner Societies.

}, doi = {10.1039/c4cp06043a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84924871719\&doi=10.1039\%2fc4cp06043a\&partnerID=40\&md5=5ba501a3bc8173c197c220cbd9af7eec}, author = {Chen, B.-J. and Tsai, P.-Y. and Huang, T.-K. and Xia, Z.-H. and Lin, K.-C. and Chiou, C.-J. and Sun, B.-J. and A.H.H. Chang} } @article {Dhenadhayalan2015, title = {Chemically Induced Fluorescence Switching of Carbon-Dots and Its Multiple Logic Gate Implementation}, journal = {Scientific Reports}, volume = {5}, year = {2015}, note = {

cited By 42

}, abstract = {

Investigations were carried out on the carbon-dots (C-dots) based fluorescent off - on (Fe 3 {\texteuro}{\textperthousand}+ {\texteuro}{\textperthousand} - S 2 O 3 2 {\textquoteright}) and on - off (Zn 2 {\texteuro}{\textperthousand}+ {\texteuro}{\textperthousand} - PO 4 3 {\textquoteright}) sensors for the detection of metal ions and anions. The sensor system exhibits excellent selectivity and sensitivity towards the detection of biologically important Fe 3 {\texteuro}{\textperthousand}+ {\texteuro}{\textperthousand}, Zn 2 {\texteuro}{\textperthousand}+ {\texteuro}{\textperthousand} metal ions and S 2 O 3 2 {\textquoteright}, PO 4 3 {\textquoteright} anions. It was found that the functional group on the C-dots surface plays crucial role in metal ions and anions detection. Inspired by the sensing results, we demonstrate C-dots based molecular logic gates operation using metal ions and anions as the chemical input. Herein, YES, NOT, OR, XOR and IMPLICATION (IMP) logic gates were constructed based on the selection of metal ions and anions as inputs. This carbon-dots sensor can be utilized as various logic gates at the molecular level and it will show better applicability for the next generation of molecular logic gates. Their promising properties of C-dots may open up a new paradigm for establishing the chemical logic gates via fluorescent chemosensors.

}, doi = {10.1038/srep10012}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84929012665\&doi=10.1038\%2fsrep10012\&partnerID=40\&md5=1d65bdd82615a7a616fe4e642c94bad6}, author = {Dhenadhayalan, N. and Lin, K.-C.} } @article {Li2015, title = {Communication: Photodissociation of CH3CHO at 308 nm: Observation of H-roaming, CH3-roaming, and transition state pathways together along the ground state surface}, journal = {Journal of Chemical Physics}, volume = {142}, number = {4}, year = {2015}, note = {

cited By 13

}, abstract = {

Following photodissociation of acetaldehyde (CH3CHO) at 308 nm, the CO(v = 1-4) fragment is acquired using time-resolved Fourier-transform infrared emission spectroscopy. The CO(v = 1) rotational distribution shows a bimodal feature; the low- and high-J components result from H-roaming around CH3CO core and CH3-roaming around CHO radical, respectively, in consistency with a recent assignment by Kable and co-workers (Lee et al., Chem. Sci. 5, 4633 (2014)). The H-roaming pathway disappears at the CO(v 2) states, because of insufficient available energy following bond-breaking of H + CH3CO. By analyzing the CH4 emission spectrum, we obtained a bimodal vibrational distribution; the low-energy component is ascribed to the transition state (TS) pathway, consistent with prediction by quasiclassical trajectory calculations, while the high-energy component results from H- and CH3-roamings. A branching fraction of H-roaming/CH3-roaming/TS contribution is evaluated to be (8\% {\textpm} 3\%)/(68\% {\textpm} 10\%)/(25\% {\textpm} 5\%), in which the TS pathway was observed for the first time. The three pathways proceed concomitantly along the electronic ground state surface. {\textcopyright} 2015 AIP Publishing LLC.

}, keywords = {Chemical reactions, Electronic ground state, Emission spectroscopy, Ground state, Ground-state surface, High-energy components, Low-energy components, Photodissociation, Quasi-classical-trajectory calculations, Rotational distributions, Time-resolved Fourier transform infrared, Vibrational distribution}, doi = {10.1063/1.4906457}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84923816206\&doi=10.1063\%2f1.4906457\&partnerID=40\&md5=99b098dc7381aebd6e798d5f12579e2b}, author = {Li, H.-K. and Tsai, P.-Y. and Hung, K.-C. and Kasai, T. and Lin, K.-C.} } @article {Nakamura201577, title = {Dynamical, spectroscopic and computational imaging of bond breaking in photodissociation: Roaming and role of conical intersections}, journal = {Faraday Discussions}, volume = {177}, year = {2015}, note = {

cited By 19

}, pages = {77-98}, abstract = {

Recent experimental and theoretical advances in the study of the dissociation of excited molecules are revealing unexpected mechanisms, when their outcomes are tackled by combining (i) space-time ion imaging of translational features, with (ii) spectroscopic probing of rotational and vibrational distributions; crucial is the assistance of (iii) the quantum chemistry of structural investigations of rearrangements of chemical bonds, and of (iv) the simulations of molecular dynamics to follow the evolution of selective bond stretching and breaking. Here we present results of such an integrated approach to methyl formate, HCOOCH3, the simplest of esters; the main focus is on the rotovibrationally excited CO (v = 1) product and in general on the energy distribution in the fragments. Previous laser studies of dissociation into CO and CH3OH at a sequence of various wavelengths discovered signatures of a roaming mechanism by the late arrival of CO (v = 0) products in time-of-flight ion imaging. Subsequent detailed investigations as a function of excitation energy provided the assessment of the threshold, which opens for triple breakdown into CO and further fragments H and CH3O, as spectroscopically characterized by ion imaging and FTIR respectively. Accompanying quantum mechanical electronic structure calculations and classical molecular dynamics simulations clarify the origin of these fragments through "roaming" pathways involving incipient radical intermediates at energies below the triple fragmentation threshold: a specific role is played by nonadiabatic transitions at a conical intersection between ground and excited states; alternative pathways focalize our attention to regions of the potential energy surfaces other than those in the neighbourhoods of saddle points along minimum energy paths: eventually this leads us to look for avenues in reaction kinetics beyond those of venerable transition state theories. This journal is {\textcopyright} The Royal Society of Chemistry.

}, keywords = {carbon monoxide, Chemistry, ELECTRON, ELECTRONS, formic acid derivative, Formic Acid Esters, Fourier Transform Infrared, infrared spectroscopy, kinetics, Mass, mass spectrometry, Matrix-Assisted Laser Desorption-Ionization, methanol, methyl formate, molecular dynamics, Molecular Dynamics Simulation, Photolysis, quantum theory, Spectrometry, SPECTROSCOPY, thermodynamics, vibration}, doi = {10.1039/c4fd00174e}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84928112000\&doi=10.1039\%2fc4fd00174e\&partnerID=40\&md5=c4888164760a43adc95cdbca1fef3a51}, author = {Nakamura, M. and Tsai, P.-Y. and Kasai, T. and Lin, K.-C. and Palazzetti, F. and Lombardi, A. and Aquilanti, V.} } @article {Veerakumar201523448, title = {Highly stable ruthenium nanoparticles on 3D mesoporous carbon: An excellent opportunity for reduction reactions}, journal = {Journal of Materials Chemistry A}, volume = {3}, number = {46}, year = {2015}, note = {

cited By 10

}, pages = {23448-23457}, abstract = {

Carbon mesoporous materials (CPMs) have great potential in the field of heterogeneous catalysis. Highly dispersed ruthenium nanoparticles (RuNPs) embedded in three dimensional (3D) CPMs as catalysts with a high surface area (1474 m2 g-1) were prepared by microwave-thermal reduction processes. Characterization technologies including X-ray diffraction (XRD), N2 adsorption/desorption isotherm measurements, field emission transmission electron microscopy (FE-TEM), thermogravimetric analysis (TGA), hydrogen temperature-programmed reduction (H2-TPR), Raman spectroscopy and 13C solid state cross polarization and magic angle spinning (13C CP/MAS) NMR spectroscopy were utilized to scrutinize the catalysts. It was revealed that the Ru/CPM catalysts exhibited a highly ordered 3D mesoporous structure and a large surface area and were widely used as catalysts for reduction reactions. Reduction of p-nitroaniline (p-NA) and crystal violet (CV) using NaBH4 with the use of this catalyst was studied by means of UV-vis spectroscopy. Here, NaBH4 acts as a hydrogen donor. This catalyst shows an excellent catalytic activity towards reduction of p-NA and CV dye at room temperature. Due to the promising properties of CPMs, they can be utilized to fabricate 3D carbon-based materials for a variety of novel applications. {\textcopyright} The Royal Society of Chemistry 2015.

}, keywords = {Adsorption/desorption, C (programming language), Carbon based materials, Catalysis, Catalyst activity, Catalysts, Characterization, Field-emission transmission electron microscopies, High resolution transmission electron microscopy, Hydrogen temperature programmed reduction, Isotherm measurement, Magic angle spinning, Mesoporous materials, Mesoporous structures, Metal nanoparticles, NANOPARTICLES, Nuclear magnetic resonance spectroscopy, Ruthenium, Ruthenium Nanoparticles, Thermogravimetric analysis, Threedimensional (3-d), Transmission electron microscopy, Ultraviolet visible spectroscopy, X ray diffraction}, doi = {10.1039/c5ta06875d}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84947755175\&doi=10.1039\%2fc5ta06875d\&partnerID=40\&md5=c94306bec7a57e2c8a5692f578adae70}, author = {P. Veerakumar and Dhenadhayalan, N. and Lin, K.-C. and Liu, S.-B.} } @article {Tsai201519592, title = {Insight into photofragment vector correlation by a multi-center impulsive model}, journal = {Physical Chemistry Chemical Physics}, volume = {17}, number = {29}, year = {2015}, note = {

cited By 4

}, pages = {19592-19601}, abstract = {

A multi-center impulsive model has been recently developed to characterize the dynamic feature of product energy distribution in photodissociation of formaldehyde, H2CO {\textrightarrow} CO + H2. (J. Phys. Chem. A, 2015, 119, 29) The model is extended to predict the vector correlations among transition dipole moment μ of the parent molecule, recoil velocity v and rotational angular momentum j of the fragments produced via the transition state (TS) and roaming path. The correlation results of μ-j, j-j and μ-v vectors of the fragments are consistent with those reported using quasi-classical trajectory simulation on the global potential energy surface. In contrast to the TS route, the vector properties via the roaming path are loosely correlated. This work offers an alternative method to study stereodynamics of the photodissociation process, and is conducive to clarifying the origin of photofragment vector correlation especially for the roaming pathway. This journal is {\textcopyright} the Owner Societies.

}, doi = {10.1039/c5cp03079j}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84937116846\&doi=10.1039\%2fc5cp03079j\&partnerID=40\&md5=98429d5f322b2683a4ab029b05c3bcf1}, author = {Tsai, P.-Y. and Lin, K.-C.} } @article {Tsai201529, title = {Insight into the photodissociation dynamical feature of conventional transition state and roaming pathways by an impulsive model}, journal = {Journal of Physical Chemistry A}, volume = {119}, number = {1}, year = {2015}, note = {

cited By 9

}, pages = {29-38}, abstract = {

Without the need to construct complicated potential energy surfaces, a multicenter impulsive model is developed to characterize the dynamical feature of conventional transition state (TS) and roaming pathways in the photodissociation of formaldehyde, H2CO {\textrightarrow} CO + H2. The photofragment energy distributions (PED) resulting from the roaming mechanism are found to closely correlate to a particular configuration that lies close to the edge of the plateau-like intrinsic reaction coordinate, whereas such a PED is associated with the configuration at the saddle point when the conventional TS pathway is followed. The evaluated PED results are consistent with those by experimental findings and quasi-classical trajectory calculations. Following impulsive analysis, the roaming pathway can be viewed as a consequence of energy transfer events between several vibrational modes. For H2CO, the available energy initially accumulated at the C-H bond is transferred to other transitional mode(s) via stretching-bending coupling, and finally to the HH stretching. (Chemical Presented). {\textcopyright} 2014 American Chemical Society.

}, keywords = {Available energy, Chemical reactions, Conventional transitions, Dynamical features, Energy distributions, Energy transfer, Intrinsic reaction coordinate, Photodissociation, Potential energy, Quantum chemistry, Quasi-classical-trajectory calculations, Transitional modes, Vibrational modes}, doi = {10.1021/jp511000t}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84920711908\&doi=10.1021\%2fjp511000t\&partnerID=40\&md5=2d26546acc9acd689419fc384ad5e995}, author = {Tsai, P.-Y. and Lin, K.-C.} } @article {Lee20154926, title = {Metal ion induced fluorescence resonance energy transfer between crown ether functionalized quantum dots and rhodamine B: Selectivity of K+ ion}, journal = {RSC Advances}, volume = {5}, number = {7}, year = {2015}, note = {

cited By 7

}, pages = {4926-4933}, abstract = {

We report a ratiometric fluorescent metal ion sensor based on the mechanism of fluorescence resonance energy transfer (FRET) between synthesized 15-crown-5-ether capped CdSe/ZnS quantum dots (QDCE) and 15-crown-5-ether attached rhodamine B (RBCE) in pH 8.3 buffer solution. Fluorescence titration with different metal ions in pH 8.3 buffer solution of the QDCE-RBCE conjugate showed a decrease and an increase in the fluorescence intensity for QDCE and RBCE moieties respectively due to FRET from QDCE to RBCE. This sensor system shows excellent selectivity towards K+ ions resulting in increasing efficiency of FRET. Energy transfer efficiency depends on the affinity between metal ions and crown ether functionalized with QDCE/RBCE. The detailed analysis of FRET was explored. This water soluble ratiometric sensor system can act as a good FRET probe for sensing applications especially in biological systems. {\textcopyright} The Royal Society of Chemistry 2015.

}, keywords = {CdSe/ZnS quantum dots, Crown ethers, Energy transfer, Energy transfer efficiency, Ethers, Fluorescence, Fluorescence intensities, Fluorescence Resonance Energy Transfer, Fluorescence titrations, Ligands, Metal ion sensors, Metal ions, METALS, Ratiometric sensors, Semiconductor quantum dots, Sensing applications}, doi = {10.1039/c4ra10925b}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84919772387\&doi=10.1039\%2fc4ra10925b\&partnerID=40\&md5=9c9e6c2fc89065fe8088f2110f6e22d0}, author = {Lee, H.-L. and Dhenadhayalan, N. and Lin, K.-C.} } @conference {Lin2015, title = {Photodissociation of methyl formate: Conical intersections, roaming and triple fragmentation}, booktitle = {AIP Conference Proceedings}, volume = {1702}, year = {2015}, note = {

cited By 1

}, abstract = {

The photodissociation channels of methyl formate have been extensively investigated by two different advanced experimental techniques, ion imaging and Fourier-Transform-Infrared emission spectroscopy, combined with quantum chemical calculations and molecular dynamics simulations. Our aim is to characterize the role of alternative routes to the conventional transition-state mediated pathway: the roaming and the triple fragmentation processes. The photolysis experiments, carried out at a range of laser wavelengths in the vicinity of the triple fragmentation threshold, beside the simulation of large bunches of classical trajectories with different initial conditions, have shown that both mechanisms share a common path that involves a conical intersection during the relaxation process from the electronic excited state S1 to the ground state S0. {\textcopyright} 2015 AIP Publishing LLC.

}, doi = {10.1063/1.4938833}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84984573015\&doi=10.1063\%2f1.4938833\&partnerID=40\&md5=113d2a7406a18d735222e37586eb8fb0}, author = {Lin, K.-C. and Tsai, P.-Y. and Chao, M.-H. and Kasai, T. and Lombardi, A. and Palazzetti, F. and Aquilanti, V.} } @article {Tsai201523112, title = {Roaming as the dominant mechanism for molecular products in the photodissociation of large aliphatic aldehydes}, journal = {Physical Chemistry Chemical Physics}, volume = {17}, number = {35}, year = {2015}, note = {

cited By 12

}, pages = {23112-23120}, abstract = {

Photodissociation of isobutyraldehyde (C3H7CHO) at 248 nm is investigated using time-resolved Fourier-transform infrared emission spectroscopy to demonstrate the growing importance of the roaming pathway with increasing molecular size of aliphatic aldehydes. Each acquired CO rotational distribution from v = 1 to 4 is well characterized by a single Boltzmann rotational temperature from 637 to 750 K, corresponding to an average rotational energy of 5.9 {\textpm} 0.6 kJ mol-1. The roaming signature that shows a small fraction of CO rotational energy disposal accompanied by a vibrationally hot C3H8 co-fragment is supported by theoretical prediction. The energy difference between the tight transition state (TS) and the roaming saddle point (SP) is found to be -27, 4, 15, 22, and 30 kJ mol-1 for formaldehyde, acetaldehyde, propionaldehyde, isobutyraldehyde, and 2,2-dimethyl propanal, respectively. The roaming SP is stabilized by a larger alkyl moiety. It is suggested that the roaming photodissociation rate of aldehydes increasingly exceeds those via the tight TS, resulting in the dominance of the CO + alkane products, as the size of aldehydes becomes larger. Along with formaldehyde, acetaldehyde, and propionaldehyde, in this work isobutyraldehyde is further demonstrated that this aldehyde family with special functional group is the first case in the organic compound to follow predominantly a roaming dissociation pathway, as the molecular size becomes larger. {\textcopyright} the Owner Societies 2015.

}, doi = {10.1039/c5cp03408f}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84940416467\&doi=10.1039\%2fc5cp03408f\&partnerID=40\&md5=1ff2eacfa2dec0b735bb7e108a59f2cc}, author = {Tsai, P.-Y. and Li, H.-K. and Kasai, T. and Lin, K.-C.} } @conference {Kasai2015, title = {Stereodynamics: From elementary processes to macroscopic chemical reactions}, booktitle = {AIP Conference Proceedings}, volume = {1702}, year = {2015}, note = {

cited By 3

}, abstract = {

This paper aims at discussing new facets on stereodynamical behaviors in chemical reactions, i.e. the effects of molecular orientation and alignment on reactive processes. Further topics on macroscopic processes involving deviations from Arrhenius behavior in the temperature dependence of chemical reactions and chirality effects in collisions are also discussed. {\textcopyright} 2015 AIP Publishing LLC.

}, doi = {10.1063/1.4938831}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84984535890\&doi=10.1063\%2f1.4938831\&partnerID=40\&md5=50b8a128e64807738f09a173820ddb62}, author = {Kasai, T. and Che, D.-C. and Tsai, P.-Y. and Lin, K.-C. and Palazzetti, F. and Aquilanti, V.} } @article {Kasai20149776, title = {Directions of chemical change: Experimental characterization of the stereodynamics of photodissociation and reactive processes}, journal = {Physical Chemistry Chemical Physics}, volume = {16}, number = {21}, year = {2014}, note = {

cited By 25

}, pages = {9776-9790}, abstract = {

This perspective article aims at accounting for the versatility of some current experimental investigations for exploring novel paths in chemical reactions. It updates a previous one [Phys. Chem. Chem. Phys., 2005, 5, 291] and is limited to work by the authors. The use of advanced molecular beam techniques together with a combination of modern tools for specific preparation, selection and detection permits us to discover new trends in reactivity in the gas phase as well as at interfaces. We specifically discuss new facets of stereodynamics, namely the effects of molecular orientation and alignment on reactive and photodissociation processes. Further topics involve roaming paths and triple fragmentation in photodissociation probed by imaging techniques, chirality effects in collisions and deviations from Arrhenius behavior in the temperature dependence of chemical reactions. {\textcopyright} the Partner Organisations 2014.

}, doi = {10.1039/c4cp00464g}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84899856354\&doi=10.1039\%2fc4cp00464g\&partnerID=40\&md5=7ce09fca11695889e3ca8323170efa00}, author = {Kasai, T. and Che, D.-C. and Okada, M. and Tsai, P.-Y. and Lin, K.-C. and Palazzetti, F. and Aquilanti, V.} } @article {Yao20141, title = {DNA interaction probed by evanescent wave cavity ring-down absorption spectroscopy via functionalized gold nanoparticles}, journal = {Analytica Chimica Acta}, volume = {820}, year = {2014}, note = {

cited By 1

}, pages = {1-8}, abstract = {

Evanescent wave cavity ring-down absorption spectroscopy (EW-CRDS) is employed to study interaction and binding kinetics of DNA strands by using gold nanoparticles (Au NPs) as sensitive reporters. These Au NPs are connected to target DNA of study that hybridizes with the complementary DNA fixed on the silica surface. By the absorbance of Au NPs, the interaction between two DNA strands may be examined to yield an adsorption equilibrium constant of 2.2{\texttimes}1010M-1 using Langmuir fit. The binding efficiency that is affected by ion concentration, buffer pH and temperature is also examined. This approach is then applied to the label-free detection of the DNA mutation diseases using the sandwich hybridization assay. For monitoring a gene associated with sickle-cell anemia, the detection limit and the adsorption equilibrium constant is determined to be 1.2pM and (3.7{\textpm}0.8){\texttimes}1010M-1, distinct difference from the perfectly matched DNA sequence that yields the corresponding 0.5pM and (1.1{\textpm}0.2){\texttimes}1011M-1. The EW-CRDS method appears to have great potential for the investigation of the kinetics of a wide range of biological reactions. {\textcopyright} 2014 Elsevier B.V.

}, keywords = {Absorption spectroscopy, Adsorption isotherms, Article, binding affinity, binding assay, binding kinetics, Cavity ring-down, complementary DNA, DNA, DNA binding, DNA denaturation, DNA determination, DNA hybridization, DNA interaction, DNA sensing, DNA sequence, DNA strand, Electromagnetic wave reflection, equilibrium constant, Equilibrium constants, evanescent wave cavity ring down absorption spectroscopy, GOLD, Gold alloys, gold nanoparticle, Gold nanoparticles, hemoglobin, hemoglobin gene, hybridization, ionic strength, limit of detection, Metal nanoparticles, pH, priority journal, sandwich hybridization assay, sickle cell anemia, Sickle cell disease, silicon dioxide}, doi = {10.1016/j.aca.2014.01.045}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84898646295\&doi=10.1016\%2fj.aca.2014.01.045\&partnerID=40\&md5=ecc7a82cdcb626321f22c277ad27a307}, author = {Yao, Y.-J. and Lin, K.-C.} } @conference {Lin2014, title = {Evanescent wave cavity ring-down spectroscopy in application to chemical and biological sensing}, booktitle = {Laser Science, LS 2014}, year = {2014}, note = {

cited By 0

}, abstract = {

Evanescent wave cavity ring-down absorption spectroscopy is applied to investigate thermodynamics, kinetics, orientation of the substrates on the surface, probe critical hemimicelle concentration of surfactants, and examine interaction and binding kinetics of DNA strands. {\textcopyright} 2014 OSA.

}, keywords = {Absorption spectroscopy, binding kinetics, Cavity ring-down, Cavity ring-down spectroscopy, Chemical and biological sensing, DNA strands, Electromagnetic wave reflection, Evanescent wave, Hemimicelle, Light measurement, thermodynamics}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84919754698\&partnerID=40\&md5=24565aba14587068285be0f23e0f9d16}, author = {Lin, K.-C.} } @article {Lin20147184, title = {Molecular halogen elimination from halogen-containing compounds in the atmosphere}, journal = {Physical Chemistry Chemical Physics}, volume = {16}, number = {16}, year = {2014}, note = {

cited By 8

}, pages = {7184-7198}, abstract = {

Atmospheric halogen chemistry has drawn much attention, because the halogen atom (X) playing a catalytic role may cause severe stratospheric ozone depletion. Atomic X elimination from X-containing hydrocarbons is recognized as the major primary dissociation process upon UV-light irradiation, whereas direct elimination of the X2 product has been seldom discussed or remained a controversial issue. This account is intended to review the detection of X2 primary products using cavity ring-down absorption spectroscopy in the photolysis at 248 nm of a variety of X-containing compounds, focusing on bromomethanes (CH2Br2, CF2Br2, CHBr2Cl, and CHBr3), dibromoethanes (1,1-C 2H4Br2 and 1,2-C2H 4Br2) and dibromoethylenes (1,1-C2H 2Br2 and 1,2-C2H2Br2), diiodomethane (CH2I2), thionyl chloride (SOCl 2), and sulfuryl chloride (SO2Cl2), along with a brief discussion on acyl bromides (BrCOCOBr and CH2BrCOBr). The optical spectra, quantum yields, and vibrational population distributions of the X2 fragments have been characterized, especially for Br2 and I2. With the aid of ab initio calculations of potential energies and rate constants, the detailed photodissociation mechanisms may be comprehended. Such studies are fundamentally important to gain insight into the dissociation dynamics and may also practically help to assess the halogen-related environmental variation. This journal is {\textcopyright} the Partner Organisations 2014.

}, doi = {10.1039/c3cp54828g}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84897065318\&doi=10.1039\%2fc3cp54828g\&partnerID=40\&md5=57fac2236e8e54b050bb0042557fb3a7}, author = {Lin, K.-C. and Tsai, P.-Y.} } @article {Lin2014, title = {Photodissociation of CH3CHO at 248 nm by time-resolved Fourier-transform infrared emission spectroscopy: Verification of roaming and triple fragmentation}, journal = {Journal of Chemical Physics}, volume = {140}, number = {6}, year = {2014}, note = {

cited By 15

}, abstract = {

By using time-resolved Fourier-transform infrared emission spectroscopy, the HCO fragment dissociated from acetaldehyde (CH3CHO) at 248 nm is found to partially decompose to H and CO. The fragment yields are enhanced by the Ar addition that facilitates the collision-induced internal conversion. The channels to CH2CO + H2 and CH3CO + H are not detected significantly. The rotational population distribution of CO, after removing the Ar collision effect, shows a bimodal feature comprising both low- and high-rotational (J) components, sharing a fraction of 19\% and 81\%, respectively, for the vibrational state v = 1. The low-J component is ascribed to both roaming pathway and triple fragmentation. They are determined to have a branching ratio of \<0.13 and \>0.06, respectively, relative to the whole v = 1 population. The CO roaming is accompanied by a highly vibrational population of CH4 that yields a vibrational bimodality. {\textcopyright} 2014 AIP Publishing LLC.

}, keywords = {Ar collisions, Branching ratio, Emission spectroscopy, Fourier transform infra reds, Internal conversions, Physical chemistry, PHYSICS, Time-resolved, Vibrational population, Vibrational state}, doi = {10.1063/1.4862266}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84907224513\&doi=10.1063\%2f1.4862266\&partnerID=40\&md5=e416a64253c3ded86e7427bbd35ae493}, author = {Lin, K.-C. and Hung, K.-C. and Tsai, P.-Y. and Li, H.-K.} } @article {Tsai2014190, title = {Photodissociation of propionaldehyde at 248 nm: Roaming pathway as an increasingly important role in large aliphatic aldehydes}, journal = {Journal of Physical Chemistry Letters}, volume = {5}, number = {1}, year = {2014}, note = {

cited By 21

}, pages = {190-195}, abstract = {

Time-resolved Fourier transform infrared emission spectroscopy is employed in the photolysis of propionaldehyde (CH3CH2CHO) at 248 nm to characterize the role of the roaming pathway. High-resolution spectra of CO are analyzed to yield a single Boltzmann rotational distribution for each vibrational level (ν = 1-4) with small rotational and large vibrational energy disposals. A roaming saddle point is found containing two far separated moieties of HCO and CH3CH2 with a weak interaction between them. Quasiclassical trajectory calculations on this configuration yield the CO energy flow behavior, consistent with the findings. The rate constant along the roaming pathway is evaluated to be larger by \>1-2 orders of magnitude than those along tight transition state or three-body dissociation pathways. This work implies that the roaming mechanism plays an increasingly important role in aliphatic aldehydes as the molecular size becomes larger. {\textcopyright} 2013 American Chemical Society.

}, keywords = {Aldehydes, Chemical reactions, Emission spectroscopy, Fourier transform infrared spectroscopy, FTIR, High-resolution spectra, Photodissociation, Photolysis, Propionaldehyde, Quasi-classical-trajectory calculations, Quasiclassical trajectories, Rate constants, roaming, Rotational distributions, Time-resolved Fourier transform infrared}, doi = {10.1021/jz402329g}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84891784599\&doi=10.1021\%2fjz402329g\&partnerID=40\&md5=4e39a3eaef20c83fcf53207426a6b3f5}, author = {Tsai, P.-Y. and Hung, K.-C. and Li, H.-K. and Lin, K.-C.} } @article {Tsai20142854, title = {Roads leading to roam. Role of triple fragmentation and of conical intersections in photochemical reactions: Experiments and theory on methyl formate}, journal = {Physical Chemistry Chemical Physics}, volume = {16}, number = {7}, year = {2014}, note = {

cited By 32

}, pages = {2854-2865}, abstract = {

The exploration of alternative roads that open to molecules with sufficient energy to yield different products permits prediction and eventually control of the outcomes of chemical reactions. Advanced imaging techniques for monitoring laser-induced photodissociation are here combined with dynamical simulations, involving ample sets of classical trajectories generated on a quantum chemical potential energy surface. Methyl formate, HCOOCH3, is photodissociated at energies near the triple fragmentation threshold into H, CO and OCH3. Images of velocity and rotational distributions of CO exhibit signatures of alternative routes, such as those recently designated as transition-state vs. roaming-mediated. Furthermore, a demonstration of the triple fragmentation route is given, and also confirmed by H-atom product imaging and FTIR time-resolved spectra of the intermediate HCO radical. In addition, the relevance of nonadiabatic transitions promoted by a conical intersection is clarified by simulations as the privileged "reactivity funnel" of organic photochemistry, whereby the outcomes of molecular photoexcitation are delivered to electronic ground states. This journal is {\textcopyright} the Owner Societies 2014.

}, doi = {10.1039/c3cp53792g}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84891796316\&doi=10.1039\%2fc3cp53792g\&partnerID=40\&md5=1044d437e26d5cc2a5058f267e4bf0a1}, author = {Tsai, P.-Y. and Chao, M.-H. and Kasai, T. and Lin, K.-C. and Lombardi, A. and Palazzetti, F. and Aquilanti, V.} } @article {Palazzetti2013299, title = {Aligned molecules: Chirality discrimination in photodissociation and in molecular dynamics}, journal = {Rendiconti Lincei}, volume = {24}, number = {3}, year = {2013}, note = {

cited By 17

}, pages = {299-308}, abstract = {

Emergence of biochemical homochirality is an intriguing topic, and none of the proposed scenarios has encountered a unanimous consensus. Candidates for naturally occurring processes, which may originate chiral selection, involve interaction of matter with light and molecular collisions. We performed and report here: (1) simulations of photodissociation of an oriented chiral molecule by linearly polarized (achiral) light observing that the angular distribution of the photofragments is characteristic of each enantiomer and both differ from the racemic mixture; and (2) molecular dynamics simulations (elastic collisions of oriented hydrogen peroxide, one of the most simple chiral molecules, with Ne atom) demonstrating that the scattering and the recoil angles are specific of the enantiomeric form. The efficacy of non-chiral light (in the case of photodissociation) and of non-chiral projectile (in the case of collisions) is due to the molecular orientation, as an essential requirement to observe chiral effects. The results of the simulations, that we report in this article, provide the background for the perspective realization of experiments which go beyond the well-documented ones involving interaction of circularly polarized laser (chiral light) with the matter, specifically by making use of non-chiral, i.e. linearly polarized or unpolarized light sources, and also by obtaining chiral effects with no use at all of light, but simply inducing them by molecular collisions. The case of vortices is discussed in a companion paper. {\textcopyright} 2013 Accademia Nazionale dei Lincei.

}, keywords = {Chemical reactions, Chirality, Circularly polarized lasers, Elastic collision, Enantiomers, Enantioselection, Light sources, Linearly polarized, Molecular collisions, molecular dynamics, Molecular dynamics simulations, Molecular orientation, MOLECULES, Naturally occurring, Photodissociation, Polarization, Stereochemistry, Trajectory simulation}, doi = {10.1007/s12210-013-0248-y}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84883487598\&doi=10.1007\%2fs12210-013-0248-y\&partnerID=40\&md5=1f9e04afa72a1cea956e0f2811a9d5b0}, author = {Palazzetti, F. and Tsai, P.-Y. and Lombardi, A. and Nakamura, M. and Che, D.-C. and Kasai, T. and Lin, K.-C. and Aquilanti, V.} } @article {Nakamura20138157, title = {Alignment selection of the metastable CO(a 3π1) molecule and the steric effect in the aligned CO(a 3π1) + NO collision}, journal = {Journal of Physical Chemistry A}, volume = {117}, number = {34}, year = {2013}, note = {

cited By 6

}, pages = {8157-8162}, abstract = {

The aligned metastable CO(a 3π1) molecular beam was generated by an electronic excitation through the Cameron band (CO a 3Π1 {\textleftarrow} X 1Σ+) transition. Beam characterization of the aligned molecular beam of CO(a 3Π1) was carried out by (1 + 1) REMPI detection via the b 3Σ+ state. The REMPI signals showed the clear dependence on the polarization of the pump laser, and the experimental result was well reproduced by the theoretical simulation. This agreement confirms that aligned metastable CO(a 3Π1) can be generated and controlled by rotating polarization of the pump laser. By using this technique, a single quantum state of CO(a 3Π1) can be selected as a metastable molecular beam. The steric effect in the energy-transfer collision of CO(a 3Π1) with NO forming the excited NO was carried out with this aligned CO(a 3Π1) molecular beam. We find that the sideways orientation of CO(a 3Π1) is more favorable in the formation of the excited NO(A 2Σ+, B 2Π) than that for the axial collisions. The obtained steric effect was discussed with the aid of the spatial distribution of CO(a 3Π1) molecular orbitals, and we find that specific rotational motion of CO(a 3Π1) in each state may not be a dominant factor in this energy-transfer collision. {\textcopyright} 2013 American Chemical Society.

}, keywords = {Axial collision, Beam characterization, Dominant factor, Electronic excitation, Energy-transfer collisions, Molecular beams, Molecular orbitals, Polarization, Pumping (laser), quantum theory, Rotational motion, Single quantum, Theoretical simulation}, doi = {10.1021/jp401784k}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84883351602\&doi=10.1021\%2fjp401784k\&partnerID=40\&md5=71543ffd44f0a15547475a5668022523}, author = {Nakamura, M. and Che, D.-C. and Tsai, P.-Y. and Lin, K.-C. and Kasai, T.} } @article {Hsu2013936, title = {Competitive bond rupture in the photodissociation of bromoacetyl chloride and 2- and 3-bromopropionyl chloride: Adiabatic versus diabatic dissociation}, journal = {ChemPhysChem}, volume = {14}, number = {5}, year = {2013}, note = {

cited By 0

}, pages = {936-945}, abstract = {

Competitive bond dissociation mechanisms for bromoacetyl chloride and 2- and 3-bromopropionyl chloride following the 1[n(O) {\textrightarrow}π*(C{\"\i}{\textsterling}O)] transition at 234-235 nm are investigated. Branching ratios for C-Br/C-Cl bond fission are found by using the (2+1) resonance-enhanced multiphoton ionization (REMPI) technique coupled with velocity ion imaging. The fragment branching ratios depend mainly on the dissociation pathways and the distances between the orbitals of Br and the C{\"\i}{\textsterling}O chromophore. C-Cl bond fission is anticipated to follow an adiabatic potential surface for a strong diabatic coupling between the n(O)π*(C{\"\i}{\textsterling}O) and np(Cl)σ*(C-Cl) bands. In contrast, C-Br bond fission is subject to much weaker coupling between n(O)π*(C{\"\i}{\textsterling}O) and np(Br)σ*(C-Br). Thus, a diabatic pathway is preferred for bromoacetyl chloride and 2-bromopropionyl chloride, which leads to excited-state products. For 3-bromopropionyl chloride, the available energy is not high enough to reach the excited-state products such that C-Br bond fission must proceed through an adiabatic pathway with severe suppression by nonadiabatic coupling. The fragment translational energies and anisotropy parameters for the three molecules are also analyzed and appropriately interpreted. Busted open: Insight into the mechanisms causing C-Cl and C-Br bond fission of bromoacetyl chloride and 2- and 3-bromopropionyl chloride by following the 1[n(O) {\textrightarrow}π*(C{\"\i}{\textsterling}O)] transition is obtained. The figure shows the center-of-mass translational energy distributions of ground-state Br formation through a diabatic pathway for the dissociation of 2-bromopropionyl chloride. Copyright {\textcopyright} 2013 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim.

}, doi = {10.1002/cphc.201200957}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84875333038\&doi=10.1002\%2fcphc.201200957\&partnerID=40\&md5=2bcc186a59909b10206fcd02b2944e8c}, author = {Hsu, M.-Y. and Tsai, P.-Y. and Wei, Z.-R. and Chao, M.-H. and Zhang, B. and Kasai, T. and Lin, K.-C.} } @article {Chao20138119, title = {Decoherence cross-section in NO + Ar collisions: Experimental results and a simple model}, journal = {Journal of Physical Chemistry A}, volume = {117}, number = {34}, year = {2013}, note = {

cited By 2

}, pages = {8119-8125}, abstract = {

Quantum decoherence can be viewed as the mechanism responsible for the quantum-to-classical transition as the initially prepared quantum state interacts with its environment in an irreversible manner. One of the most common mechanisms responsible for the macroscopically observed decoherence involves collisions of an atom or molecule, initially prepared in a coherent superposition of states, with gas particles. In this work, a coherent superposition of quantum internal states of NO molecules is prepared by the interaction between the molecule with both a static and a radiofrequency electric field. Subsequently, NO + Ar collision decoherence experiments are investigated by measuring the loss of coherence as a function of the number of collisions. Data analysis using a model based on the interaction potential of the collisional partners allowed to unravel the molecular mechanism responsible for the loss of coherence in the prepared NO quantum superposition of internal states. The relevance of the present work relies on several aspects. On the one hand, the use of radio-waves introduces a new way for the production of coherent beams. On the other hand, the employed methodology could be useful in investigating the Stereodynamics of chemical reactions with coherent reagents. {\textcopyright} 2013 American Chemical Society.

}, keywords = {Coherent superpositions, Electric fields, Interaction potentials, Model-based OPC, Molecular mechanism, MOLECULES, Quantum decoherence, Quantum superpositions, quantum theory, Quantum to classical transition, Radio frequency electric field}, doi = {10.1021/jp401005v}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84883333000\&doi=10.1021\%2fjp401005v\&partnerID=40\&md5=7a7e2dd8392475465ea08d48c4a14d38}, author = {Chao, M.-S. and Tornero, J. and K.C. Lin and Stolte, S. and Gonz{\'a}lez Ure{\~n}a, A.} } @article {Chang20131064, title = {Interfacial electron transfer from CdSe/ZnS quantum dots to TiO2 nanoparticles: Linker dependence at single molecule level}, journal = {Electroanalysis}, volume = {25}, number = {4}, year = {2013}, note = {

cited By 2

}, pages = {1064-1073}, abstract = {

We utilize single molecule spectroscopy combined with time-correlated single-photon counting to probe electron transfer (ET) kinetics from CdSe/ZnS (core/shell) quantum dots (QDs) to TiO2 through various lengths of linker molecules. The QD-linker-TiO2 complexes with varied linker length, linker structure, and QD size are fabricated by a surface-based stepwise method to show control of the rate and of the magnitude of fluctuations of photo-induced ET at the single molecule level. The ET rate constants are determined to be 2.8{\texttimes}107, 1.9{\texttimes}107, and 3.5{\texttimes}106s-1 for the chain length of 1.5, 6.2 and 13.8{\r A}, respectively. The electronic coupling strengths between QDs and TiO2 are further calculated to be 3.68, 3.60, and 1.59cm-1 for the three different chain lengths by using the Marcus ET model. {\textcopyright} 2013 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim.

}, doi = {10.1002/elan.201200618}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84876305724\&doi=10.1002\%2felan.201200618\&partnerID=40\&md5=19ed5b9857a562b6b8a20c7966f564c2}, author = {Chang, Y.-P. and Tsai, P.-Y. and Lee, H.-L. and Lin, K.-C.} } @article {Tsai2013, title = {Note: Photodissociation of CH3COCN at 308 nm by time-resolved Fourier-transform infrared emission spectroscopy: Is CO a primary or secondary product?}, journal = {Journal of Chemical Physics}, volume = {138}, number = {24}, year = {2013}, note = {

cited By 1

}, abstract = {

This Note aims to clarify the source of CO in photodissociation of acetyl cyanide (CH3COCN) at 308 nm. From the theoretical aspects, a new pathway via isomerization transition state (TS) at 391 {\textpm} 8 kJ/mol is found leading to the CO + CH3NC products. An amount of 60\% reactant molecules at 300 K is estimated to successfully surpass the average TS barrier lying above the excitation energy by 3.5 kJ/mol. Further, a prior distribution method is conducted to characterize the vibrational energy distribution of CO on a statistical basis. The pathway to CH3NC + CO yields a vibrational branching ratio (v = 0:v = 1:v = 2:v = 3\~{}0.63:0.25:0.093:0.032) in excellent agreement with the observation (0.62:0.25:0.09:0.05). {\textcopyright} 2013 AIP Publishing LLC.

}, keywords = {Branching ratio, carbon monoxide, Chemical reactions, Chemistry, cyanide, Cyanides, Emission spectroscopy, Fourier transform infra reds, Fourier Transform Infrared, infrared spectroscopy, letter, Photochemical Processes, PHOTOCHEMISTRY, Photodissociation, Prior distribution, Reactant molecules, Secondary product, SPECTROSCOPY, Theoretical aspects, TIME, Time Factors, Transition state, Vibrational energy distribution}, doi = {10.1063/1.4812378}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84879913792\&doi=10.1063\%2f1.4812378\&partnerID=40\&md5=bbc6634ce42a1501a43d1e43de04a145}, author = {Tsai, P.-Y. and Lin, K.-C.} } @article {Hu2013, title = {Photodissociation of gaseous CH3COSH at 248 nm by time-resolved Fourier-transform infrared emission spectroscopy: Observation of three dissociation channels}, journal = {Journal of Chemical Physics}, volume = {138}, number = {1}, year = {2013}, note = {

cited By 8

}, abstract = {

Upon one-photon excitation at 248 nm, gaseous CH3C(O)SH is dissociated following three pathways with the products of (1) OCS + CH 4, (2) CH3SH + CO, and (3) CH2CO + H 2S that are detected using time-resolved Fourier-transform infrared emission spectroscopy. The excited state 1(nO, π *CO) has a radiative lifetime of 249 {\textpm} 11 ns long enough to allow for Ar collisions that induce internal conversion and enhance the fragment yields. The rate constant of collision-induced internal conversion is estimated to be 1.1 {\texttimes} 10-10 cm3 molecule -1 s-1. Among the primary dissociation products, a fraction of the CH2CO moiety may undergo further decomposition to CH2 + CO, of which CH2 is confirmed by reaction with O2 producing CO2, CO, OH, and H2CO. Such a secondary decomposition was not observed previously in the Ar matrix-isolated experiments. The high-resolution spectra of CO are analyzed to determine the ro-vibrational energy deposition of 8.7 {\textpm} 0.7 kcal/mol, while the remaining primary products with smaller rotational constants are recognized but cannot be spectrally resolved. The CO fragment detected is mainly ascribed to the primary production. A prior distribution method is applied to predict the vibrational distribution of CO that is consistent with the experimental findings. {\textcopyright} 2013 American Institute of Physics.

}, keywords = {Ar collisions, Carbon dioxide, DISSOCIATION, Dissociation channels, Dissociation products, Emission spectroscopy, High-resolution spectra, Infrared emission spectroscopy, Internal conversions, One-photon excitation, Primary production, Prior distribution, quantum theory, Radiative lifetime, Rate constants, Ro-vibrational energies, Rotational constants, Secondary decomposition, Time-resolved, Vibrational distribution}, doi = {10.1063/1.4768872}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84872089893\&doi=10.1063\%2f1.4768872\&partnerID=40\&md5=4a228cd7d97e90783940137b5fb77340}, author = {Hu, E.-L. and Tsai, P.-Y. and Fan, H. and Lin, K.-C.} } @article {Yeh2012, title = {Gas-phase photodissociation of CH 3COCN at 308 nm by time-resolved Fourier-transform infrared emission spectroscopy}, journal = {Journal of Chemical Physics}, volume = {136}, number = {4}, year = {2012}, note = {

cited By 10

}, abstract = {

By using time-resolved Fourier-transform infrared emission spectroscopy, the fragments of HCN(v 1, 2) and CO(v 1-3) are detected in one-photon dissociation of acetyl cyanide (CH 3COCN) at 308 nm. The S 1(A "), 1(n O, π CO) state at 308 nm has a radiative lifetime of 0.46 {\textpm} 0.01 μs, long enough to allow for Ar collisions that induce internal conversion and enhance the fragment yields. The rate constant of Ar collision-induced internal conversion is estimated to be (1-7) {\texttimes} 10 -12 cm 3 molecule -1 s -1. The measurements of O 2 dependence exclude the production possibility of these fragments via intersystem crossing. The high-resolution spectra of HCN and CO are analyzed to determine the ro-vibrational energy deposition of 81 {\textpm} 7 and 32 {\textpm} 3 kJmol, respectively. With the aid of ab initio calculations, a two-body dissociation on the energetic ground state is favored leading to HCN CH 2CO, in which the CH 2CO moiety may further undergo secondary dissociation to release CO. The production of CO 2 in the reaction with O 2 confirms existence of CH 2 and a secondary reaction product of CO. The HNC fragment is identified but cannot be assigned, as restricted to a poor signal-to-noise ratio. Because of insufficient excitation energy at 308 nm, the CN and CH 3 fragments that dominate the dissociation products at 193 nm are not detected. {\textcopyright} 2012 American Institute of Physics.

}, keywords = {ab initio calculations, Ar collisions, Carbon dioxide, Cyanides, DISSOCIATION, Dissociation products, Emission spectroscopy, Gasphase, High-resolution spectra, Infrared emission spectroscopy, Internal conversions, Intersystem crossing, quantum theory, Radiative lifetime, Rate constants, Ro-vibrational energies, Secondary dissociation, Secondary reactions, Time-resolved}, doi = {10.1063/1.3674166}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84861591481\&doi=10.1063\%2f1.3674166\&partnerID=40\&md5=1975ee8e0bbb54261ac72c7e3352e54c}, author = {Yeh, Y.-Y. and Chao, M.-H. and Tsai, P.-Y. and Chang, Y.-B. and Tsai, M.-T. and Lin, K.-C.} } @article {Lin201241, title = {Interaction between crystal violet and anionic surfactants at silica/water interface using evanescent wave-cavity ring-down absorption spectroscopy}, journal = {Journal of Colloid and Interface Science}, volume = {379}, number = {1}, year = {2012}, note = {

cited By 4

}, pages = {41-47}, abstract = {

Evanescent wave-cavity ring-down spectroscopy (EW-CRDS) is employed to characterize micellization of anionic surfactants and the related capability of removing cationic substance off the silica surface. Crystal violet (CV +) cationic dye is used as a molecular probe to effectively determine critical hemimicelle concentration (HMC) of surfactants on the surface. The HMC results are 1{\texttimes}10 -2, 4{\texttimes}10 -3, 8{\texttimes}10 -4, and 2.5{\texttimes}10 -4mol/L for sodium sulfate salts with a carbon-chain length of C-10, C-12, C-14, and C-16, respectively. A stronger hydrophobic interaction results in a less concentration required to undergo micellization. The HMC values on the surface are about half of those in solution. When NaCl solution is added, the electrolyte helps reduce the electrostatic repulsion between the anionic sulfate heads to facilitate the surfactant aggregation, and thus, the subsequent HMC is reduced. Furthermore, the probable phase change for dye-surfactant interactions on the surface at the concentration below HMC is observed, and the desorption rates of CV + are measured as a function of concentration and carbon-chain length of surfactants above HMC. Given each surfactant concentration at its respective HMC, the corresponding desorption rates are along the order of C-12\<C-14\<C-16\<-C-10. The trend may be realized by two competing factors of hemimicelle size and number density. The consequences help with understanding how to apply surfactant in the chromatographic separation. {\textcopyright} 2012 Elsevier Inc.

}, keywords = {Absorption spectroscopy, ADSORPTION, Anionic surfactants, aqueous solution, Article, Biophysics, carbon, Carbon-chain length, Cationic dyes, Chain length, Chromatographic separations, concentration (parameters), Crystal violet, DESORPTION, Desorption rate, Dye-surfactant interaction, Dyes, electric conductivity, Electromagnetic wave reflection, Electrostatic repulsion, EW-CRDS, Hydrophobic interactions, hydrophobicity, Interfacial adsorption, Liquid chromatography, Micellization, molecular interaction, Molecular Probes, NaCl solution, Number density, Phase Change, priority journal, Ringdown spectroscopy, Silica, Silica surface, silicon dioxide, Sodium chloride, SPECTROSCOPY, Surface active agents, Surfactant, Surfactant aggregation, Surfactant concentrations, water}, doi = {10.1016/j.jcis.2012.04.041}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84861948384\&doi=10.1016\%2fj.jcis.2012.04.041\&partnerID=40\&md5=92ed762990e7749d0421ee55e5bc94a4}, author = {M.-C. Lin and Lin, K.-C.} } @article {Chang20122711, title = {Interfacial electron transfer from CdSe/ZnS quantum dots to TiO 2 nanoparticles: Size dependence at the single-molecule level}, journal = {ChemPhysChem}, volume = {13}, number = {11}, year = {2012}, note = {

cited By 4

}, pages = {2711-2720}, abstract = {

Electron transfer (ET) kinetics of CdSe/ZnS core/shell quantum dots (QDs) on bare coverslips and a TiO 2 nanoparticle-coated thin film has been investigated at the single-molecule level. The QDs prepared have three different diameters of 3.6, 4.6, and 6.4 nm. The trajectories of fluorescence intensity are acquired with respect to the arrival time. The on-time events and subsequent fluorescence lifetimes are shorter with decreasing size. Given the lifetime measurements for QDs on glass and TiO 2, the rate constant of ET from QDs to TiO 2 may be determined to be 1.3{\texttimes}10 7, 6.0{\texttimes}10 6, and 4.7{\texttimes}10 6 s -1 for the increasing sizes of the QDs. The plot of on-time probability density versus arrival time is characterized by power-law statistics in the short time region and a bending tail in the long time region. Marcus{\textquoteright}s ET model is employed to satisfactorily fit the bending tail behavior and to further calculate the ET rate constants. The theoretical counterparts for the different sizes are 1.4{\texttimes}10 7, 6.4{\texttimes}10 6, and 1.9{\texttimes}10 6 s -1, showing good agreement with the experimental results. Going dotty: Electron transfer kinetics of CdSe/ZnS core/shell quantum dots (QDs) on bare coverslips and on TiO 2 nanoparticle coated thin films have been investigated at the single-molecule level. As the size of the QDs changes, the shift in the valence band (VB) energy is less significant than the shift in the conduction band (CB) energy. Copyright {\textcopyright} 2012 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim.

}, doi = {10.1002/cphc.201200037}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84864415806\&doi=10.1002\%2fcphc.201200037\&partnerID=40\&md5=507ed7b2b463a925e4414e5b836a76f1}, author = {C.-L. Chang and Tsai, P.-Y. and Chang, Y.-P. and Lin, K.-C.} } @article {Fan2012, title = {Molecular elimination of Br2 in photodissociation of CH 2BrC(O)Br at 248 nm using cavity ring-down absorption spectroscopy}, journal = {Journal of Chemical Physics}, volume = {137}, number = {21}, year = {2012}, note = {

cited By 3

}, abstract = {

The primary elimination channel of bromine molecule in one-photon dissociation of CH2BrC(O)Br at 248 nm is investigated using cavity ring-down absorption spectroscopy. By means of spectral simulation, the ratio of nascent vibrational population in v 0, 1, and 2 levels is evaluated to be 1:(0.5 {\textpm} 0.1):(0.2 {\textpm} 0.1), corresponding to a Boltzmann vibrational temperature of 581 {\textpm} 45 K. The quantum yield of the ground state Br2 elimination reaction is determined to be 0.24 {\textpm} 0.08. With the aid of ab initio potential energy calculations, the obtained Br2 fragments are anticipated to dissociate on the electronic ground state, yielding vibrationally hot Br2 products. The temperature-dependence measurements support the proposed pathway via internal conversion. For comparison, the Br2 yields are obtained analogously from CH3CHBrC(O)Br and (CH3)2CBrC(O)Br to be 0.03 and 0.06, respectively. The trend of Br2 yields among the three compounds is consistent with the branching ratio evaluation by Rice-Ramsperger-Kassel-Marcus method. However, the latter result for each molecule is smaller by an order of magnitude than the yield findings. A non-statistical pathway so-called roaming process might be an alternative to the Br2 production, and its contribution might account for the underestimate of the branching ratio calculations. {\textcopyright} 2012 American Institute of Physics.

}, keywords = {Ab initio, Boltzmann, Branching ratio, Bromine, Bromine compounds, CALCULATIONS, Cavity ring-down, Chemical reactions, Electronic ground state, Elimination reaction, Energy calculation, Ground state, Internal conversions, Molecular elimination, MOLECULES, Quantum yield, Rice-ramsperger-kassel-marcus, Spectral simulations, Temperature dependence, Vibrational population, Vibrational temperature}, doi = {10.1063/1.4767346}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84870884930\&doi=10.1063\%2f1.4767346\&partnerID=40\&md5=54a7aeece77aa2edd7830b83113f7a58}, author = {Fan, H. and Tsai, P.-Y. and Lin, K.-C. and Lin, C.-W. and Yan, C.-Y. and Yang, S.-W. and A.H.H. Chang} } @article {Kasai2012567, title = {Reaction dynamics with molecular beams and oriented molecular beams: A tool for looking closer to chemical reactions and photodissociations}, journal = {Journal of the Chinese Chemical Society}, volume = {59}, number = {5}, year = {2012}, note = {

cited By 2

}, pages = {567-582}, abstract = {

Experimental studies on reaction dynamics by use of molecular beams and oriented molecular beams are reviewed in order for looking closer to chemical reactions as well as photodissociations at the molecular level. We discuss about versatility and usefulness of the electrostatic hexapole sate-selector as a non-destructive selector for molecular structure analysis. Some experimental evidences on novel reaction dynamics in photodissociation and stereodynamics are presented followed by concluding remarks and future perspectives for controlling chemical reactions from the point of view of green chemistry, by manipulating molecular orientation without any catalyst nor by applying any external forces like intense electromagnetic field. {\textcopyright} 2012 The Chemical Society Located in Taipei \& Wiley-VCH Verlag GmbH \& Co. KGaA, Weinheim.

}, doi = {10.1002/jccs.201100735}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84861646610\&doi=10.1002\%2fjccs.201100735\&partnerID=40\&md5=50be00023ed35e692203398efda0522c}, author = {Kasai, T. and Che, D.-C. and Tsaia, P.-Y. and Lina, K.-C.} } @article {Tsai2012274, title = {Rotational energy transfer of SH(X 2 Π, v'=0, J'=0.5-10.5) by collision with Ar: λ-doublet resolved transition propensity}, journal = {ChemPhysChem}, volume = {13}, number = {1}, year = {2012}, note = {

cited By 0

}, pages = {274-280}, abstract = {

The behavior of λ-doublet resolved rotational energy transfer (RET) by Ar collisions within the SH(X 2Π, v'=0) state is characterized. The matrix elements of terms in the interaction potential responsible for interference effects are calculated to explain the propensity rules for collision-induced transitions within and between spin-orbit manifolds. In this manner, the physical mechanisms responsible for the F 1-F 1, F 2-F 2, and F 1-F 2 transitions may be reasonably identified. As collision energy increases, the propensity for collisional population of the final e or f level is replaced by the e/f-conserving propensity. Such a change in propensity rule can be predicted in terms of energy sudden approximation at high J limit for the pure Hund{\textquoteright}s case scheme. Copyright {\textcopyright} 2012 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim.

}, doi = {10.1002/cphc.201100604}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84855660091\&doi=10.1002\%2fcphc.201100604\&partnerID=40\&md5=befcd64fbb5e8ee6e9aa7e0982ab950e}, author = {Tsai, P.-Y. and Lin, K.-C.} } @article {Wu2011, title = {Br 2 molecular elimination in photolysis of (COBr) 2 at 248 nm by using cavity ring-down absorption spectroscopy: A photodissociation channel being ignored}, journal = {Journal of Chemical Physics}, volume = {135}, number = {23}, year = {2011}, note = {

cited By 6

}, abstract = {

A primary dissociation channel of Br 2 elimination is detected following a single-photon absorption of (COBr) 2 at 248 nm by using cavity ring-down absorption spectroscopy. The technique contains two laser beams propagating in a perpendicular configuration. The tunable laser beam along the axis of the ring-down cell probes the Br 2 fragment in the B 3Π + ou-X 1Σ g + transition. The measurements of laser energy- and pressure-dependence and addition of a Br scavenger are further carried out to rule out the probability of Br 2 contribution from a secondary reaction. By means of spectral simulation, the ratio of nascent vibrational population for v = 0, 1, and 2 levels is evaluated to be 1:(0.65 {\textpm} 0.09):(0.34 {\textpm} 0.07), corresponding to a Boltzmann vibrational temperature of 893 {\textpm} 31 K. The quantum yield of the ground state Br 2 elimination reaction is determined to be 0.11 {\textpm} 0.06. With the aid of ab initio potential energy calculations, the pathway of molecular elimination is proposed on the energetic ground state (COBr) 2 via internal conversion. A four-center dissociation mechanism is followed synchronously or sequentially yielding three fragments of Br 2 + 2CO. The resulting Br 2 is anticipated to be vibrationally hot. The measurement of a positive temperature effect supports the proposed mechanism. {\textcopyright} 2011 American Institute of Physics.

}, keywords = {Ab initio, Boltzmann, CALCULATIONS, Cavity ring-down, Chemical reactions, Dissociation channels, Dissociation mechanisms, Elimination reaction, Energy calculation, Ground state, Internal conversions, Laser beams, Laser energies, Lasers, Molecular elimination, Multiphoton processes, Photodissociation, Photolysis, Pressure dependence, quantum theory, Quantum yield, Ring-down cells, Secondary reactions, Single-photon absorptions, Spectral simulations, Vibrational population, Vibrational temperature}, doi = {10.1063/1.3664782}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84555202652\&doi=10.1063\%2f1.3664782\&partnerID=40\&md5=ed9be908f408948f0d734a7449622cc2}, author = {Wu, C.-C. and Lin, H.-C. and Chang, Y.-B. and Tsai, P.-Y. and Yeh, Y.-Y. and Fan, H. and Lin, K.-C. and Francisco, J.S.} } @article {Tsai20118857, title = {Doublet rotational energy transfer of the SH (X 2Π, v'' = 0) state by collisions with Ar}, journal = {Physical Chemistry Chemical Physics}, volume = {13}, number = {19}, year = {2011}, note = {

cited By 1

}, pages = {8857-8868}, abstract = {

The rotational energy transfer (RET) by Ar collisions within the SH X 2Π (v'' = 0, J'' = 0.5-10.5) state is characterized. The integral cross sections as a function of collision energy for each rotational transition are calculated using a quantum scattering method in which the constructed potential energy functions are based on a ground state potential energy surface (PES) reported previously. On the other hand, a laser-induced excitation fluorescence technique is employed to monitor the relaxation of the rotational population as a function of photolysis-probe delay time following the photodissociation of H2S at 248 nm. The rotational population evolution is comparable to its theoretical counterpart based on calculated Λ-resolved RET rate constants. The propensity in Λ-resolved RET transitions is found to approximately resemble the case of OH(X 2Π, v'' = 0) + Ar. The Λ-averaged RET collisions are also analyzed and result in several propensity rules in the transitions. Most propensity rules are similar to those observed in the collisions of SH(A 2Σ+) by Ar. However, the behavior of the conserving ratio, defined as rate constants for spin-orbit conserving transition divided by those for spin-orbit changing transition, shows distinct difference from those described by Hund{\textquoteright}s case (b). {\textcopyright} the Owner Societies.

}, doi = {10.1039/c0cp01882a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-79955530591\&doi=10.1039\%2fc0cp01882a\&partnerID=40\&md5=28fe652ac95f0c61e222f90d4f98f397}, author = {Tsai, P.-Y. and Lin, K.-C.} } @article {Liu2011206, title = {Gas-phase photodissociation of CH3CHBrCOCl at 248 nm: Detection of molecular fragments by time-resolved FT-IR spectroscopy}, journal = {ChemPhysChem}, volume = {12}, number = {1}, year = {2011}, note = {

cited By 6

}, pages = {206-216}, abstract = {

By employing time-resolved Fourier transform infrared emission spectroscopy, the fragments HCl (v=1-3), HBr (v=1), and CO (v=1-3) are detected in one-photon dissociation of 2-bromopropionyl chloride (CH3CHBrCOCl) at 248 nm. Ar gas is added to induce internal conversion and to enhance the fragment yields. The time-resolved high-resolution spectra of HCl and CO were analyzed to determine the rovibrational energy deposition of 10.0A {\textpm}0.2 and 7.4A {\textpm}0.6 kcal mol-1, respectively, while the rotational energy in HBr is evaluated to be 0.9A {\textpm}0.1 kcal mol-1. The branching ratio of HCl(v\>0)/HBr(v\>0) is estimated to be 1:0.53. The bond selectivity of halide formation in the photolysis follows the same trend as the halogen atom elimination. The probability of HCl contribution from a hot Cl reaction with the precursor is negligible according to the measurements of HCl amount by adding an active reagent, Br2, in the system. The HCl elimination channel under Ar addition is verified to be slower by two orders of magnitude than the Cl elimination channel. With the aid of ab initio calculations, the observed fragments are dissociated from the hot ground state CH3CHBrCOCl. A two-body dissociation channel is favored leading to either HCl+CH3CBrCO or HBr+CH2CHCOCl, in which the CH 3CBrCO moiety may further undergo secondary dissociation to release CO. {\textcopyright} 2011 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim.

}, keywords = {Article, Chemistry, Fourier Transform Infrared, GAS, Gases, infrared spectroscopy, Photochemical Processes, PHOTOCHEMISTRY, Propionates, propionic acid derivative, SPECTROSCOPY, ultraviolet radiation, Ultraviolet Rays}, doi = {10.1002/cphc.201000713}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-78651465375\&doi=10.1002\%2fcphc.201000713\&partnerID=40\&md5=4eafd36cfc057962701338de1b1ad684}, author = {Liu, C.-Y. and Tsai, M.-T. and Tsai, P.-Y. and Liu, Y.-T. and Chen, S. Y. and A.H.H. Chang and Lin, K.-C.} } @article {Kao20112328, title = {Hydrogen-bonding-induced one-handed helical polynorbornenes appended with chiral alaninegland}, journal = {Macromolecular Chemistry and Physics}, volume = {212}, number = {21}, year = {2011}, note = {

cited By 2

}, pages = {2328-2338}, abstract = {

Polynorbornenes appended with anthracene and chiral alanine linkers are synthesized. Hydrogen bonding between the adjacent bisamidic linkers brings adjacent anthracene chromophores in a more suitable orientation for exciton coupling and renders one-handed helical structures for these polymers. Excimer formation is observed from their emission spectra. Monoamidic linkers provide only one hydrogen bond, which would be less robust and result in much lower circular dichroic response. Hydrogen bonding between the adjacent chiral alanine linkers brings appended anthracene in a more suitable orientation for exciton coupling and excimer formation, rendering one-handed helical structures in polynorbornenes. {\textcopyright} 2011 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim.

}, keywords = {alanine pendants, Amino acids, Anthracene, chromophores, Dichroic response, Dichroism, Emission spectroscopy, Emission spectrums, Excimer formation, Exciton coupling, EXCITONS, Helical structures, hydrogen, Hydrogen bondings, hydrogen bonds, One-handed, polynorbornenes}, doi = {10.1002/macp.201100471}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-80455177195\&doi=10.1002\%2fmacp.201100471\&partnerID=40\&md5=b9bb7c91a96e36aeccfa79c348ffe7de}, author = {Kao, M.-J. and C.-H. Chen and Tsai, P.-Y. and Lim, T.-S. and Lin, K.-C. and Luh, T.-Y.} } @article {Chen2011, title = {I2 molecular elimination in single-photon dissociation of CH2I2 at 248 nm by using cavity ring-down absorption spectroscopy}, journal = {Journal of Chemical Physics}, volume = {134}, number = {3}, year = {2011}, note = {

cited By 10

}, abstract = {

Following single-photon dissociation of CH2I2 at 248 nm, I2 molecular elimination is detected by using cavity ring-down absorption spectroscopy. The technique comprises two laser beams propagating in a perpendicular configuration, in which a tunable laser beam along the axis of the ring-down cell probes the I2 fragment in the B 3 ou + - X 1 g + transition. The nascent vibrational populations for v 0, 1, and 2 levels are obtained with a population ratio of 1:(0.65 0.10):(0.30 0.05), corresponding to a Boltzmann-like vibrational temperature of 544 73 K. The quantum yield of the ground state I2 elimination reaction is determined to be 0.0040 0.0025. With the aid of ab initio potential energy calculations, the pathway of molecular elimination is proposed on the energetic ground state CH2I2 via internal conversion, followed by asynchronous three-center dissociation. A positive temperature effect supports the proposed mechanism. {\textcopyright} 2011 American Institute of Physics.

}, keywords = {Ab initio, ABSORPTION, Absorption spectroscopy, Article, Boltzmann, Cavity ring-down, Chemistry, DISSOCIATION, Elimination reaction, Energy calculation, Ground state, Hydrocarbons, Internal conversions, Iodinated, iodinated hydrocarbon, iodine, Laser beams, Lasers, methylene iodide, Molecular elimination, Multiphoton processes, Particle beams, photon, Photons, Population ratio, quantum theory, Quantum yield, Ring-down cells, Single-photon dissociation, Spectrophotometry, Temperature, Temperature effects, Tunable lasers, Ultraviolet, ultraviolet spectrophotometry, Vibrational population, Vibrational temperature}, doi = {10.1063/1.3523571}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-79551624294\&doi=10.1063\%2f1.3523571\&partnerID=40\&md5=baffccd8329095529a0c82c7ea2930e3}, author = {S.-Y. Chen and Tsai, P.-Y. and Lin, H.-C. and Wu, C.-C. and Lin, K.-C. and Sun, B.J. and A.H.H. Chang} } @article {Chao20117154, title = {Molecular elimination of methyl formate in photolysis at 234 nm: Roaming vs. transition state-type mechanism}, journal = {Physical Chemistry Chemical Physics}, volume = {13}, number = {15}, year = {2011}, note = {

cited By 21

}, pages = {7154-7161}, abstract = {

Ion imaging coupled with (2 + 1) resonance-enhanced multiphoton ionization (REMPI) technique is employed to probe CO(v" = 0) fragments at different rotational levels following photodissociation of methyl formate (HCOOCH 3) at 234 nm. When the rotational level, J"CO, is larger than 24, only a broad translational energy distribution extending beyond 70 kcal mol-1 with an average energy of about 23 kcal mol -1 appears. The dissociation process is initiated on the energetic ground state HCOOCH3 that surpasses a tight transition state along the reaction coordinate prior to breaking into CO + CH3OH. This molecular dissociation pathway accounts for the CO fragment with larger rotational energy and large translational energy. As J"CO decreases, a bimodal distribution arises with one broad component and the other sharp component carrying the average energy of only 1-2 kcal mol-1. The branching ratio of the sharp component increases with a decrease of J"CO; (7.3 {\textpm} 0.6)\% is reached as the image is probed at J"CO = 10. The production of a sharp component is ascribed to a roaming mechanism that has the following features: a small total translational energy, a low rotational energy partitioning in CO, but a large internal energy in the CH3OH co-product. The internal energy deposition in the fragments shows distinct difference from those via the conventional transition state. {\textcopyright} the Owner Societies 2011.

}, doi = {10.1039/c0cp02710c}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84859755272\&doi=10.1039\%2fc0cp02710c\&partnerID=40\&md5=f9b74194dca995352a60ad2537c49019}, author = {Chao, M.-H. and Tsai, P.-Y. and Lin, K.-C.} } @article {Tsai20111419, title = {Orientation dependence for Br formation in the reaction of oriented OH radical with HBr molecule}, journal = {Physical Chemistry Chemical Physics}, volume = {13}, number = {4}, year = {2011}, note = {

cited By 23

}, pages = {1419-1423}, abstract = {

The orientation dependence of Br-atom formation in the reaction of the oriented OH radical with the HBr molecule using the hexapole electrostatic field was studied. Experimental results for the orientation dependence in the reaction were analyzed using a Legendre polynomial fit. The results show two reactive sites. It was found that O-end attack is most favored for this reaction, and that H-end attack also shows a pronounced reactivity. The reactivity of the side-ways attack was found to be small. By comparing the results of the orientation dependence in the reaction with studies of inelastic collisions and theoretical calculations, two reaction pathways are proposed. Reaction by O-end attack is followed by a direct abstraction of the H-atom from the HBr molecule. The mechanism for H-end attack may have H-atom migration from HBr to form the water molecule. {\textcopyright} 2011 the Owner Societies.

}, keywords = {Article, Bromine, Chemistry, hydrobromic acid, hydroxyl radical, OXYGEN, static electricity}, doi = {10.1039/c0cp01089h}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-78651315433\&doi=10.1039\%2fc0cp01089h\&partnerID=40\&md5=2618335a61130eb81c5c9949b64456b7}, author = {Tsai, P.-Y. and Che, D.-C. and Nakamura, M. and Lin, K.-C. and Kasai, T.} } @article {Hsiao2011, title = {Quasiclassical trajectory calculations for Li(22PJ) H2 {\textrightarrow} LiH(X1) H: Influence by vibrational excitation and translational energy}, journal = {Journal of Chemical Physics}, volume = {134}, number = {3}, year = {2011}, note = {

cited By 10

}, abstract = {

Ab initio potential energy surfaces and the corresponding analytical energy functions of the ground 1A' and excited 2A' states for the Li(22P) plus H2 reaction are constructed. Quasiclassical trajectory calculations on the fitted energy functions are performed to characterize the reactions of Li(22P) with H2(v 0, j 1) and H2(v 1, j 1) as well as the reaction when the vibrational energy is replaced by collision energy. For simplicity, the transition probability is assumed to be unity when the trajectories go through the crossing seam region and change to the lower surface. The calculated rotational distributions of LiH(v 0) for both H2(v 0, j 1) and H2(v 1, j 1) reactions are single-peaked with the maximum population at j' 7, consistent with the previous observation. The vibrational excitation of H2(v 1) may enhance the reaction cross section of LiH(v' 0) by about 200 times, as compared to a result of 93-107 reported in the experimental measurements. In contrast, the enhancement is 3.1, if the same amount of energy is deposited in the translational states. This endothermic reaction can be considered as an analog of late barrier. According to the trajectory analysis, the vibrational excitation enlarges the H-H distance in the entrance channel to facilitate the reaction, but the excess energy may not open up additional reaction configuration. {\textcopyright} 2011 American Institute of Physics.

}, keywords = {Ab initio potential energy surface, Additional reactions, Collision energies, Endothermic reactions, Energy functions, Excess energy, Excited states, Experimental measurements, Lithium alloys, Quantum chemistry, Quasiclassical trajectory calculations, Reaction cross-sections, Rotational distributions, Trajectories, Trajectory analysis, Transition probabilities, Translational energy, Vibrational energies, Vibrational excitation}, doi = {10.1063/1.3519801}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-79551642554\&doi=10.1063\%2f1.3519801\&partnerID=40\&md5=32f8502b18952ac27c7881f55a2648f2}, author = {Hsiao, M.-K. and Lin, K.-C. and Hung, Y.-M.} } @article {Tsai20101162, title = {Fine structure-resolved rotational energy transfer of SH (A 2Σ+, v' = 0) state by collisions with Ar}, journal = {Physical Chemistry Chemical Physics}, volume = {12}, number = {5}, year = {2010}, note = {

cited By 2

}, pages = {1162-1171}, abstract = {

Rotational energy transfer (RET) by Ar collisions within the v' = 0 level of the SH A2Σ+ state is probed using a laser-induced dispersed fluorescence technique, following photodissociation of H2S at 248 nm. The Ar pressure is adjusted appropriately to allow for significant observation of the single-collision induced RET process. The spin-resolved and spin-averaged rate constants are then evaluated with the aid of a kinetic model under single-collision conditions. The theoretical counterparts are calculated using a quantum scattering method, in which a newly fitted potential energy function is based on ab initio potential energy surface reported previously. The experimental and theoretical kinetic data are essentially consistent in the trend of N and ΔN dependence. Several propensity rules are found in the RET collisions. For instance, for ΔN = 1, 2, and 3, the rate constants decrease with increasing N or ΔN. Given a fixed ΔN, the rate constants of the same initial N in the downward transition appear to be larger than those in the upward transitions. In ΔN = 0, the F2 {\textrightarrow} F1 transitions prevail over the F 1 {\textrightarrow} F2 transitions (F1 = N + 1/2, F 2 = N - 1/2), whereas in ΔN /= 0, the fine-structure- conserving collisions are more favored than the fine-structure-changing collisions. The principle of microscopic reversibility is also examined for both experimental and theoretical kinetic data, showing that translational energies of the RET collisions are close to thermal equilibrium at room temperature. The propensity rules may be rationalized according to this principle. {\textcopyright} 2010 the Owner Societies.

}, doi = {10.1039/b920614k}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-77955979605\&doi=10.1039\%2fb920614k\&partnerID=40\&md5=8678adff2d93cf0f2845183d3ed9a35c}, author = {Tsai, P.-Y. and Lin, K.-C.} } @article {Chen2010868, title = {Kinetic and thermodynamic investigation of rhodamine B adsorption at solid/solvent interfaces by use of evanescent-wave cavity ring-down spectroscopy}, journal = {Analytical Chemistry}, volume = {82}, number = {3}, year = {2010}, note = {

cited By 24

}, pages = {868-877}, abstract = {

Evanescent-wave cavity ring-down spectroscopy is applied to investigate the adsorption behavior of rhodamine B at three different interfaces. The adsorption equilibrium constant (Kads) and adsorption free energy of rhodamine B at the silica/methanol interface are determined to be (1.5 {\textpm} 0.2) {\texttimes} 104 M-1 and -23.8 {\textpm} 0.4 kJ/mol by use of a Langmuir isotherm model. A Langmuir-based kinetic model is also developed to determine the corresponding adsorption and desorption rate constants of (1.02 {\textpm} 0.03) {\texttimes} 102 M-1 s-1 and (7.1 {\textpm} 0.2) {\texttimes} 10-3 s-1, from which Kads is obtained to be (1.45 {\textpm} 0.09) {\texttimes} 104 M-1, in agreement with the value determined under equilibrium conditions. Similarly, when rhodamine B is at the chlorotrimethylsilane-immobilized silica/methanol interface, the adsorption and desorption rate constants are determined to be (1.7 {\textpm} 0.2) {\texttimes} 102 M-1 s-1 and (5.0 {\textpm} 1.0) {\texttimes} 10-3 s-1{\textperiodcentered} The subsequent Kads is (3.6 {\textpm} 0.4) {\texttimes} 104 M-1, which is larger than that at the silica/methanol interface. The former adsorption is dominated by hydrophobic interaction, while the latter is subject to electrostatic attraction. When rhodamine B is at the silica/water interface, there exist three chemical forms, including zwitterion (R+B -), cation (RBH+), and lactone (RBL). A combination of double-layer and Langmuir competitive models is used to fit the adsorption isotherm as a function of solution pH, yielding Kads of (2.5 {\textpm} 0.2) {\texttimes} 104 M-1 and (1.1 {\textpm} 0.2) {\texttimes} 105 M-1 for R+B- and RBH +, respectively. RBL is considered to have the same Kads value as R+B-. {\textcopyright} 2010 American Chemical Society.

}, keywords = {ADSORPTION, Adsorption behavior, Adsorption equilibrium constants, Adsorption free energy, Adsorption isotherms, Chemical forms, Chlorotrimethylsilanes, Competitive models, DESORPTION, Desorption rate constants, Double layers, Electrochemical electrodes, Electrostatic attractions, Equilibrium conditions, Equilibrium constants, Evanescent-wave cavity ring-down spectroscopy, Hydrophobic interactions, hydrophobicity, Kinetic models, Langmuir isotherm models, Langmuirs, Light measurement, Rate constants, Rhodamine B, Rhodamine B adsorption, Solution pH, Thermodynamic investigation}, doi = {10.1021/ac9020209}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-76149119433\&doi=10.1021\%2fac9020209\&partnerID=40\&md5=0a693f7126106d98a882dd4f897f192c}, author = {Chen, M.-S. and Fan, H.-F. and Lin, K.-C.} } @article {Tsai20102532, title = {Orientation dependence in the four-atom reaction of OH + HBr using the single-state oriented OH radical beam}, journal = {Physical Chemistry Chemical Physics}, volume = {12}, number = {11}, year = {2010}, note = {

cited By 23

}, pages = {2532-2534}, abstract = {

The orientation dependence for the Br atom formation in the reaction of the oriented OH radicals with HBr molecules at 0.26 eV collision energy has been observed for the first time using the hexapole electric field, and we found that the reaction cross-section for O-end attack is more favorable than that for H-end attack by a factor of 3.4 {\textpm} 2.3. {\textcopyright} the Owner Societies.

}, doi = {10.1039/b923934k}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-77749277686\&doi=10.1039\%2fb923934k\&partnerID=40\&md5=f631b2465a6117a615ba3ddaea9f798b}, author = {Tsai, P.-Y. and Che, D.-C. and Nakamura, M. and Lin, K.-C. and Kasai, T.} } @article {Liu20107275, title = {Photodissociation of gaseous acetyl chloride at 248 nm by time-resolved fourier-transform infrared spectroscopy: The HCl, CO, and CH2 product channels}, journal = {Journal of Physical Chemistry A}, volume = {114}, number = {27}, year = {2010}, note = {

cited By 12

}, pages = {7275-7283}, abstract = {

In one-photon dissociation of gaseous acetyl chloride at 248 nm, time-resolved Fourier-transform infrared emission spectroscopy is used to detect the fragments of HCl, CO, and CH2 in the presence of Ar or O 2. The high-resolution spectra of HCl and CO are analyzed to yield the corresponding internal energy deposition of 8.9 {\textpm} 1.1 and 6.2 {\textpm} 0.9 kcal/mol. The presence of the CH2 fragment is verified by detecting the CO2 product resulting from the reaction of CH 2 and the added O2. The probability of the HCl formation via a hot Cl reaction with the precursor is examined to be negligible by performing two experiments, the CH3COCl pressure dependence and the measurement of Br2 with Cl reaction. The HCl elimination channel under the Ar addition is verified to be slowed by 2 orders of magnitude, as compared to the Cl elimination channel. The observed fragments are proposed to dissociate on the hot ground electronic state via collision-induced internal conversion. A two-body dissociation channel is favored leading to HCl and CH2CO, followed by secondary dissociation. {\textcopyright} 2010 American Chemical Society.

}, keywords = {Acetates, acetic acid derivative, Acetic Acids, Acetyl chloride, argon, Article, carbon monoxide, Chemistry, chloride, Chlorides, Chlorine compounds, CL reaction, Dissociation channels, Emission spectroscopy, Fourier Transform Infrared, Fourier transforms, GAS, Gases, Ground electronic state, High-resolution spectra, hydrochloric acid, Infrared emission spectroscopy, infrared spectroscopy, Internal conversions, Internal energies, Orders of magnitude, OXYGEN, PHOTOCHEMISTRY, Photodissociation, Pressure dependence, Product channel, rotation, Secondary dissociation, SPECTROSCOPY, TIME, Time Factors, Time-resolved, vibration, Wavelet transforms}, doi = {10.1021/jp1030653}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-77954448374\&doi=10.1021\%2fjp1030653\&partnerID=40\&md5=bae7fd207ac95f19ef630f1ad94dd04b}, author = {Liu, Y.-T. and Tsai, M.-T. and Liu, C.-Y. and Tsai, P.-Y. and Lin, K.-C. and Shih, Y.H. and A.H.H. Chang} } @article {Tsai20101, title = {Photodissociation of gaseous propionyl chloride at 248 nm by time-resolved Fourier-transform infrared spectroscopy}, journal = {Chemical Physics}, volume = {376}, number = {1-3}, year = {2010}, note = {

cited By 8

}, pages = {1-9}, abstract = {

In one-photon dissociation of propionyl chloride at 248 nm, time-resolved Fourier-transform infrared emission spectroscopy is used to detect the fragments of HCl and CO in the presence of Ar. The inert gas Ar plays a role to enhance the internal conversion. The time-dependence of high-resolution HCl spectra yields a bimodal rotational distribution in the early stage. The total rotational and vibrational energy partitioned in HCl are evaluated to be 1.7 {\textpm} 0.3 and 8.8 {\textpm} 1.9 kcal/mol, respectively. The CO appearance indicates that HCl may be eliminated through a five-center mechanism accompanied with three-body dissociation of C2H2, HCl, and CO. A four-center mechanism forming HCl and CH3CHCO also contributes to the HCl fragment with a feature of rotational bimodality. However, the probability for the HCl contribution from the hot Cl reaction is negligible. The reaction with CH4 is carried out to evaluate the HCl and Cl elimination rate constants. {\textcopyright} 2010 Elsevier B.V. All rights reserved.

}, doi = {10.1016/j.chemphys.2010.06.016}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-78649632960\&doi=10.1016\%2fj.chemphys.2010.06.016\&partnerID=40\&md5=4b49bb146bfbe460a04509f66f7cfc87}, author = {Tsai, M.-T. and Liu, Y.-T. and Liu, C.-Y. and Tsai, P.-Y. and Lin, K.-C.} } @article {Chen20109050, title = {Photoinduced electron transfer of oxazine 1/TiO2 nanoparticles at single molecule level by using confocal fluorescence microscopy}, journal = {Langmuir}, volume = {26}, number = {11}, year = {2010}, note = {

cited By 6

}, pages = {9050-9060}, abstract = {

Kinetics of photoinduced electron transfer (ET) from oxazine 1 dye to TiO2 nanoparticles (NPs) surface is studied at a single molecule level by using confocal fluorescence microscopy. Upon irradiation with a pulsed laser at 630 nm, the fluorescence lifetimes sampled among 100 different dye molecules are determined to yield an average lifetime of 2.9 {\textpm} 0.3 ns, which is close to the value of 3.0 {\textpm} 0.6 ns measured on the bare coverslip. The lifetime proximity suggests that most interfacial electron transfer (IFET) processes for the current system are inefficient, probably caused by physisorption between dye and the TiO2 film. However, there might exist some molecules which are quenched before fluorescing and fail to be detected. With the aid of autocorrelation analysis under a three-level energy system, the IFET kinetics of single dye molecules in the conduction band of TiO2 NPs is evaluated to be (1.0 {\textpm} 0.1){\texttimes}104 s-1 averaged over 100 single molecules and the back ET rate constant is 4.7 {\textpm} 0.9 s-1. When a thicker TiO2 film is substituted, the resultant kinetic data do not make a significant difference. The trend of IFET efficacy agrees with the method of fluorescence lifetime measurements. The obtained forward ET rate constants are about ten times smaller than the photovoltage response measured in an assembled dye-sensitized solar cell. The discrepancy is discussed. The inhomogeneous and fluctuation characters for the IFET process are attributed to microenvironment variation for each single molecule. The obtained ET rates are much slower than the fluorescence relaxation. Such a small ET quantum yield is yet feasibly detectable at a single molecule level. {\textcopyright} 2010 American Chemical Society.

}, keywords = {Autocorrelation analysis, Average lifetime, Confocal fluorescence microscopy, Current system, Dye molecule, Dye-Sensitized solar cell, Electron mobility, Electron transitions, Energy systems, Fluorescence, Fluorescence lifetime measurements, Fluorescence lifetimes, Fluorescence microscopy, Heterojunctions, Interfacial electron transfer, Kinetic data, Microenvironments, MOLECULES, NANOPARTICLES, Nitrogen compounds, Photo-induced electron transfer, Photovoltage response, Physisorption, Pulsed laser, Pulsed laser applications, Pulsed lasers, Rate constants, Single dye molecules, Single molecule, Single molecule level, Solar cells, Three-level, TiO}, doi = {10.1021/la904273x}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-77952855207\&doi=10.1021\%2fla904273x\&partnerID=40\&md5=4c0c2dbdc32427366e505e21ba536ae5}, author = {Chen, Y.-J. and Tzeng, H.-Y. and Fan, H.-F. and Chen, M.-S. and Huang, J.-S. and Lin, K.-C.} } @book {lin2007gas, title = {Gas Phase Molecular Reaction and Photodissociation Dynamics}, series = {India}, year = {2007}, note = {

n/a

}, publisher = {Transworld Research Network}, organization = {Transworld Research Network}, abstract = {

n/a

}, author = {K.C. Lin and P. D. Kleiber} }