乙基硫自由基及阴、阳离子低电子激发态从头算研究

采用CASSCF方法和6-311++(3df, 3pd)基组以及Cs对称性优化了乙基硫自由基和阳、阴离子3种分子的12个电子态的几何构型. 利用二级微扰方法(CASPT2)对这12个电子态做了单点能校正. 通过比较自由基与阴阳离子的能量, 得出了绝热电子亲和势和绝热电子电离能, 与实验结果在允许误差范围内基本一致.

CAS Calculations on the Ground and Low-lying Excited States of Ethylthio Radical, Cation and Anion

The quantum calculations at CASPT2/CASSCF level were performed for the low-lying excited states of the ethylthio radical, cation and anion. In Cs point group geometry, total twelve electronic states were optimized at CASSCF level and the frequencies analyses were performed for these three molecules. The single point energy corrections were carried out at CASPT2 level. The adiabatic ionization energies and the electron affinity energies were obtained through the comparison between the energies of the ground state of the radical and those of the corresponding ions were made. All results obtained are consistent with the available data from the literatures.