Zuo Junxiang, Li Yongle, Guo Hua, Xie Daiqian
Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210093, China.
Department of Physics, International Center of Quantum and Molecular Structures, Shanghai Key Laboratory of High Temperature Superconductors, Shanghai University , Shanghai 200444, China.
J Phys Chem A. 2016 May 26;120(20):3433-40. doi: 10.1021/acs.jpca.6b03488. Epub 2016 May 11.
Thermal rate coefficients at temperatures between 200 and 1000 K are calculated for the HCl + OH → Cl + H2O reaction on a recently developed permutation invariant potential energy surface, using ring polymer molecular dynamics (RPMD). Large deviations from the Arrhenius limit are found at low temperatures, suggesting significant quantum tunneling. Agreement with available experimental rate coefficients is generally satisfactory, although the deviation becomes larger at lower temperatures. The theory-experiment discrepancy is attributed to the remaining errors in the potential energy surface, which is known to slightly overestimate the barrier. In the deep tunneling region, RPMD performs better than traditional transition-state theory with semiclassical tunneling corrections.
利用环聚合物分子动力学（RPMD），在最近开发的置换不变势能面上计算了200至1000K温度范围内HCl + OH → Cl + H2O反应的热速率系数。在低温下发现与阿仑尼乌斯极限有很大偏差，这表明存在显著的量子隧穿。与现有实验速率系数的一致性总体令人满意，尽管在较低温度下偏差会变大。理论与实验的差异归因于势能面中仍存在的误差，已知该势能面会略微高估势垒。在深隧穿区域，RPMD的表现优于带有半经典隧穿修正的传统过渡态理论。
