Lin Guang-Shuang-Mu, Xie Changjian, 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 Chemistry and Chemical Biology , University of New Mexico , Albuquerque , New Mexico 87131 , United States.
J Phys Chem A. 2018 Jun 21;122(24):5375-5382. doi: 10.1021/acs.jpca.8b03460. Epub 2018 Jun 12.
Nonadiabatic photodissociation dynamics of thiophenol (PhSH) and deuterated thiophenol (PhSD) via the ππ* state was investigated by a reduced three-dimensional (3D) quantum model based on the associated 3D diabatic potential energy surfaces constructed at the explicitly correlated multireference configuration interaction (MRCI-F12) level with the cc-pVTZ-F12 basis. The lifetimes of the low-lying vibronic S states for PhSH and PhSD were calculated using a low-storage filter diagonalization method and were in reasonably good agreement with the available experimental results. The nonadiabatic effect was further examined in the photodissociation process by comparing the results in diabatic and adiabatic models. It was found that the adiabatic lifetimes were about 2-4 times shorter than the exact ones in the diabatic model for both PhSH and PhSD. More importantly, the exact ground wave function including the geometric phase (GP) possessed a node along the C-C-S-H/C-C-S-D torsional coordinate, while the node was absent when GP was not included in the adiabatic model. The node structure of the wave function was a hallmark of GP, which sheds light on the nonadiabatic photodissociation dynamics facilitated by the conical intersections.
通过基于在cc-pVTZ-F12基组下显式相关多参考组态相互作用（MRCI-F12）水平构建的相关三维非绝热势能面的简化三维（3D）量子模型，研究了苯硫酚（PhSH）和氘代苯硫酚（PhSD）通过ππ*态的非绝热光解离动力学。使用低存储滤波对角化方法计算了PhSH和PhSD的低振动态S态的寿命，其与现有实验结果相当吻合。通过比较非绝热模型和绝热模型的结果，进一步研究了光解离过程中的非绝热效应。结果发现，对于PhSH和PhSD，绝热寿命比非绝热模型中的精确寿命短约2-4倍。更重要的是，包含几何相位（GP）的精确基态波函数在C-C-S-H/C-C-S-D扭转坐标上有一个节点，而在绝热模型中不包含GP时该节点不存在。波函数的节点结构是GP的一个标志，这为锥形交叉促进的非绝热光解离动力学提供了线索。
