Liu Tianhui, Zhang Zhaojun, Fu Bina, Yang Xueming, Zhang Dong H
State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China.
Phys Chem Chem Phys. 2016 Mar 28;18(12):8537-44. doi: 10.1039/c6cp00034g.
The mode-specific dynamics for the dissociative chemisorption of H2O on Cu(111) is first investigated by seven-dimensional quantum dynamics calculations, based on an accurately fitted potential energy surface (PES) recently developed by neural network fitting to DFT energy points. It is indicated that excitations in all three vibrational modes have a significant impact on reactivity, which are more efficacious than increasing the translational energy in promoting the reaction, with the largest enhancement for the excitation in the asymmetric stretching mode. There is large discrepancy between the six-dimensional reactivities with fixed azimuthal angles and seven-dimensional results, revealing that the 6D "flat surface" model cannot accurately characterize the reaction dynamics. The azimuthal angle-averaging approach is validated for vibrational excited states of the reactant, where the 7D mode-specific probability can be well reproduced by averaging the 6D azimuthal angle-fixed probabilities over 18 angles.
基于最近通过神经网络拟合DFT能量点而开发的精确拟合势能面（PES），首次通过七维量子动力学计算研究了H₂O在Cu(111)上的解离化学吸附的模式特定动力学。结果表明，所有三种振动模式的激发对反应活性都有显著影响，在促进反应方面，这些激发比增加平动能更有效，其中不对称拉伸模式的激发增强最大。固定方位角的六维反应活性与七维结果之间存在很大差异，这表明六维“平面”模型不能准确表征反应动力学。方位角平均方法在反应物振动激发态中得到验证，通过在18个角度上平均六维方位角固定概率，可以很好地再现七维模式特定概率。
