Dissociative chemisorption of methane on a nickel surface is a prototypical system for studying mode-specific chemistry in gassurface reactions.We recently developed a fifteen-dimensional potential energy surface for ...Dissociative chemisorption of methane on a nickel surface is a prototypical system for studying mode-specific chemistry in gassurface reactions.We recently developed a fifteen-dimensional potential energy surface for this system which has proven to be chemically accurate in reproducing the measured absolute dissociative sticking probabilities of CHD_3in thermal conditions and with vibrational excitation on Ni(111)at high incident energies.Here,using this new potential energy surface,we explored mode specificity and bond selectivity for CHD_3and CH_2D_2dissociative chemisorption at low incidence energies down to^50 k J/mol via a quasi-classical trajectory method.Our calculated dissociation probabilities are consistent with previous theoretical and experimental ones with an average shift in translational energy of^8 k J/mol.Our results very well reproduce the C–H/C–D branching ratio upon the C–H local mode excitation,which can be rationalized by the sudden vector projection model.Quantitatively,however,the calculated dissociative sticking probabilities are systematically larger than experimental ones,due presumably to the artificial zero point energy leakage into reaction coordinate.Further high-dimensional quantum dynamics calculations are necessary for acquiring a chemically accurate description of methane dissociative chemisorption at low incident energies.展开更多
Much progress has been achieved for both experimental and theoretical studies on the dissociative chemisorption of molecules on surfaces.Quantum state-resolved experimental data has provided unprecedented details for ...Much progress has been achieved for both experimental and theoretical studies on the dissociative chemisorption of molecules on surfaces.Quantum state-resolved experimental data has provided unprecedented details for these fundamental steps in heterogeneous catalysis,while the quantitative dynamics is still not fully understood in theory.An in-depth understanding of experimental observations relies on accurate dynamical calculations,in which the potential energy surface and adequate quantum mechanical implementation are desired.This article summarizes the current methodologies on the construction of potential energy surfaces and the quantum mechanical treatments,some of which are promising for future applications.The challenges in this field are also addressed.展开更多
I. INTRODUCTION The chemisorption characteristics and reactivity near the ledge on the stepped surface as a defect on solid surface are worth noticing. In many cases, defects on metal surface not only control the adso...I. INTRODUCTION The chemisorption characteristics and reactivity near the ledge on the stepped surface as a defect on solid surface are worth noticing. In many cases, defects on metal surface not only control the adsoprtion rate of the gas molecule, but also have an impotant influence on the formation of a veriety of catalysates. For example, studying the catalytic oxidation展开更多
Ⅰ. INTRODUCTIONSome experiments showed that after forming graphite monolayer, the catalytic activites of some metal catalysts were reduced and lost. But mechanism of this process is still poorly understood. On the ot...Ⅰ. INTRODUCTIONSome experiments showed that after forming graphite monolayer, the catalytic activites of some metal catalysts were reduced and lost. But mechanism of this process is still poorly understood. On the other hand, the reaction of hydrogengraphite system plays an important role in the field of exploiting and the use of energy source. Therefore, this system has attracted attention in further studying the kinetics of its reaction. Demidovish et al. studied EPR on the dissociative adsorption of H<sub>2</sub> on graphite surfacet. Dihydrogen recombination, being an inverse展开更多
基金supported by the National Key R&D Program of China (2017YFA0303500)the National Natural Science Foundation of China (91645202, 21722306, 21573203)+1 种基金Anhui Initiative in Quantum Information Technologiespartially supported by Fundamental Research Funds for the Central Universities (WK2060190082, WK2340000078)
文摘Dissociative chemisorption of methane on a nickel surface is a prototypical system for studying mode-specific chemistry in gassurface reactions.We recently developed a fifteen-dimensional potential energy surface for this system which has proven to be chemically accurate in reproducing the measured absolute dissociative sticking probabilities of CHD_3in thermal conditions and with vibrational excitation on Ni(111)at high incident energies.Here,using this new potential energy surface,we explored mode specificity and bond selectivity for CHD_3and CH_2D_2dissociative chemisorption at low incidence energies down to^50 k J/mol via a quasi-classical trajectory method.Our calculated dissociation probabilities are consistent with previous theoretical and experimental ones with an average shift in translational energy of^8 k J/mol.Our results very well reproduce the C–H/C–D branching ratio upon the C–H local mode excitation,which can be rationalized by the sudden vector projection model.Quantitatively,however,the calculated dissociative sticking probabilities are systematically larger than experimental ones,due presumably to the artificial zero point energy leakage into reaction coordinate.Further high-dimensional quantum dynamics calculations are necessary for acquiring a chemically accurate description of methane dissociative chemisorption at low incident energies.
基金supported by the National Natural Science Foundation of China(21133006,21273104,91221301 and 91021010)the Ministry of Science and Technology(2013CB834601)
文摘Much progress has been achieved for both experimental and theoretical studies on the dissociative chemisorption of molecules on surfaces.Quantum state-resolved experimental data has provided unprecedented details for these fundamental steps in heterogeneous catalysis,while the quantitative dynamics is still not fully understood in theory.An in-depth understanding of experimental observations relies on accurate dynamical calculations,in which the potential energy surface and adequate quantum mechanical implementation are desired.This article summarizes the current methodologies on the construction of potential energy surfaces and the quantum mechanical treatments,some of which are promising for future applications.The challenges in this field are also addressed.
基金Project supported by the National Natural Science Foundation of China
文摘I. INTRODUCTION The chemisorption characteristics and reactivity near the ledge on the stepped surface as a defect on solid surface are worth noticing. In many cases, defects on metal surface not only control the adsoprtion rate of the gas molecule, but also have an impotant influence on the formation of a veriety of catalysates. For example, studying the catalytic oxidation
基金Project supported by the National Natural Science Foundation of china.
文摘Ⅰ. INTRODUCTIONSome experiments showed that after forming graphite monolayer, the catalytic activites of some metal catalysts were reduced and lost. But mechanism of this process is still poorly understood. On the other hand, the reaction of hydrogengraphite system plays an important role in the field of exploiting and the use of energy source. Therefore, this system has attracted attention in further studying the kinetics of its reaction. Demidovish et al. studied EPR on the dissociative adsorption of H<sub>2</sub> on graphite surfacet. Dihydrogen recombination, being an inverse