摘要
三原子卤代卡宾自由基作为活性中间体,在燃烧过程、大气化学、有机合成等研究中起着至关重要的作用。我们采用包括戴维森修正的内收缩多参考组态相互作用方法(icMRCI+Q)对三原子卤代卡宾CHCl电子激发态进行了高水平从头算研究,计算了能量高达7eV的13个电子态的垂直跃迁能,振子强度,研究了不同电子激发态沿键角,CH与CCl键长的势能曲线。基于理论研究,我们对CHCl分子在波长为193nm激光下的光解动力学机制进行了深入分析,为理解电子态的复杂相互作用和行为提供重要依据。由于I的重原子特性,我们采用考虑自旋轨道耦合效应的MRCI-F12方法,计算了CHI三个最低激发态的电子结构和频率,首次研究了不同电子态在考虑与未考虑旋轨效应情况下分别沿键角,CH键长,CI键长的势能曲线。理论研究表明,单三重态在弯曲振动模式下存在强的旋轨耦合作用,并研究了自旋轨道效应对高激发态的光解动力学影响,为进一步实验工作提供理论依据。
We present a high-level ab initio study on the geometries and frequencies of electronic excited states of the CHCl using MRCI method including Davidson correction. The potential energy curves of the electronic states have been studied along the H-C-Cl angle, the C-H bond length and the C-Cl bond length, respectively. The excited state involved in the 193-nm photodissociation as well as the corresponding dissociation dynamics have been discussed based on our calculation results.We calculated the geometries and frequencies of the lowest three states of the CHI using MRCI-F12 method including spin-orbit coupling. The potential energy curves of the Λ-S and Ω states have first been studied along the H-C-I angle, the C-H bond length and the C-I bond length, respectively. The study indicated that the bending level of the X~1A' has the severely perturbed at energies above the a~3A''.
引文