用密度泛函理论计算稠环分子的极化率

摘要

Accurate DFT studies of the static dipole polarizabilities of anthracene and phenanthrene were reported. Geometries were optimized at the HF/6 -311 G (3d ,2p) level of theory. Dipole polarizabilities were calculated at the HF/6 -311 + +G(3d,2p) and B. 3LYP/6 -311 + + G(3d,2p) levels of theory, using HF/6 -311G(3d,2p) geometries. The calculated dipole polarizabilities for anthracene are compared with experiment. Examination of corresponding B3LYP results for the polyacene series benzene, naphthalene and anthracene shows that the normal component of the dipole polarizability scales linearly with the number of benzene ring units, with an incresment of20. 8 au. The medium component also scales linearly with an increment of 42. 8 atomic units. The long component does not scale linearly.%报道了用密度泛函(DFT)理论精确计算稠环烃系苯、蒽和菲分子的极化率结果.蒽和菲分子的几何构型优化采用HF/6-311G(3d,2p);极化率的计算采用B3LYP/6-311++G(3d,2p).其结果与实验值符合得较好,也与相关的稠环多烯芳香烃的实验结果进行了关联.结果发现苯、蒽和菲分子的固有的极化率数据随着苯环的增加而增加,大约增加20.8个原子单位;分子的诱导极化率的数据随着苯环的增加而成线性增加,大约增加42.8个单位;而瞬时极化率的数据却不见有什么变化.