氯代苯阳离子的密度泛函理论研究

采用B3LYP方法及6-311G(d,p)和6-311+G(d,p)基组,对12种氯代苯阳离子进行了理论研究,优化其电子基态的结构,计算了对应分子的垂直电离势(VIP)和绝热电离势(AIP).依据Jahn-Teller理论,确定了1,3,5-C6H3Cl3+和C6Cl6+离子分别具有C2v(2B1)和D2h(2B2g)结构(对应分子分别为D3h和D6h结构).其余10个离子的构型的对称点群与对应分子相同,但构型参数值有明显差别.用B3LYP方法计算的各氯代苯分子的垂直电离势和绝热电离势与实验值符合得很好.

Density Functional Theory Study on the Chlorinated Benzenes Cations

Twelve chlorinated benzenes cations were studied by the B3LYP method in conjunction with the 6-311G(d,p) and 6-311+G(d,p) basis sets. The ground-state geometries of these cations were predicted and the vertical ionization potentials(VIPs) and adiabatic ionization potentials(AIPs) of the corresponding molecules were calculated. The 1,3,5-C6H3F3+ and C6F6+ ions are the Jahn-Teller active species, and they are predicted to have C2v and D2h structures, in contrast with the D3h and D6h structures of their parent molecules, respectively. Though other ten cations have same symmetry with their respective parent molecules, the geometric parameters of cations are different with the molecules. The B3LYP calculations predict vertical and adiaba-tic ionization potential values of the chlorinated benzene molecules in good agreement with the available experimental values.