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, People's Republic of China.
J Chem Phys. 2018 Apr 14;148(14):144705. doi: 10.1063/1.5023069.
We constructed a nine-dimensional (9D) potential energy surface (PES) for the dissociative chemisorption of HO on a rigid Ni(100) surface using the neural network method based on roughly 110 000 energies obtained from extensive density functional theory (DFT) calculations. The resulting PES is accurate and smooth, based on the small fitting errors and the good agreement between the fitted PES and the direct DFT calculations. Time dependent wave packet calculations also showed that the PES is very well converged with respect to the fitting procedure. The dissociation probabilities of HO initially in the ground rovibrational state from 9D quantum dynamics calculations are quite different from the site-specific results from the seven-dimensional (7D) calculations, indicating the importance of full-dimensional quantum dynamics to quantitatively characterize this gas-surface reaction. It is found that the validity of the site-averaging approximation with exact potential holds well, where the site-averaging dissociation probability over 15 fixed impact sites obtained from 7D quantum dynamics calculations can accurately approximate the 9D dissociation probability for HO in the ground rovibrational state.
我们使用神经网络方法，基于从广泛的密度泛函理论（DFT）计算中获得的大约 110000 个能量，构建了 HO 在刚性 Ni(100)表面上离解化学吸附的九维（9D）势能面（PES）。基于较小的拟合误差和拟合 PES 与直接 DFT 计算之间的良好一致性，得到的 PES 是准确且平滑的。含时波包计算也表明，PES 在拟合过程中具有很好的收敛性。HO 最初处于基态振转态的 9D 量子动力学计算的离解概率与 7D 计算的特定位置结果有很大差异，这表明全维量子动力学对于定量描述这种气体-表面反应非常重要。研究发现，具有精确势能的位置平均近似的有效性很好，其中从 7D 量子动力学计算中得到的 15 个固定冲击位置的位置平均离解概率可以准确地近似 HO 在基态振转态的 9D 离解概率。
