报告摘要 | Rate coefficients for chemical reactions, whether in the gas phase or condensed phases, are key information for understanding complex processes such as combustion, atmospheric chemistry, and heterogeneous catalysis. Theoretical calculations of rate coefficients for elementary chemical reactions are often performed with the transition-state theory, which contains several assumptions that might fail in many situations. These assumptions include the harmonic oscillator-rigid rotor approximations, the neglect of recrossing, and perhaps most severely the approximate treatment of quantum effects (zero-point energy and tunneling). In this talk, we discuss recent progress in accurate calculations of rate coefficients for gas phase and surface reactions using the ring-polymer molecular dynamics (RPMD) approach. The RPMD theory is based on the ring-polymer Hamiltonian, in which each quantum particle is simulated by a harmonically connected necklace. This path integral based approach is capable of simulating quantum effects, while it takes advantage of the classical-like trajectories. Benchmark calculations for gas phase bimolecular reactions have demonstrated its accuracy, with relatively inexpensive computational costs. Recent focus has shifted to simulating surface reactions. We present the latest studies of H2 dissociative chemisorption and recombinative desorption on transition metal surfaces, in comparison with the latest experimental measurements. |
报告人简介 | Hua Guo is Distinguished Professor at University of New Mexico, USA. After receiving his BS degree in 1982 from Chengdu Institute of Electronic Engineering, China, he studied theoretical chemistry with Prof. Guosen Yan at Sichuan University, China, earning his MS degree in 1985. He obtained his DPhil degree in 1988 under the supervision of the late Prof. John Murrell, FRS, at Sussex University, UK. After a postdoctoral stint with Prof. George Schatz at Northwestern University, USA, he started his independent career in 1990 at the University of Toledo, USA. He moved to University of New Mexico, USA, in 1998. He has broad research interests ranging from reaction dynamics and kinetics in the gas phase and at surfaces, spectroscopy, to enzymology and heterogeneous catalysis. He has published more than 600 peer reviewed papers, with an H-index of 80. He serves on serval editorial boards, including Science, J. Phys. Chem. ABC, and Theo. Chem. Acc. He is a Fellow of American Physical Society and a Fellow of American Association for the Advancement of Sciences. He received an Alexander von Humboldt Research Award in 2020 and the Dudley Herschbach Madel (Theory) in 2023. |
