DFT Study on Structural Distortion and Vibronic Coupling of Vanadyl Porphyrin Anion and Cation  

作　　者：Hui-ling Gao Fang Chen Guo-hua Yao Dong-ming Chen 

机构地区：[1]Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China

出　　处：《Chinese Journal of Chemical Physics》2013年第5期504-511,I0003,共9页化学物理学报（英文）

摘　　要：The geometries of one-electron reduced/oxidized species （[TOP]-/[VOP] ＋） of vanadyl por- phyrin （VOP） have been calculated with PBE1PBE method. The results show that for both [VOP]- and [VOP]＋ the ground states are triplet, in which one of the two unpaired electron occupies the dxy orbital of the V atom while the other occupies the n-orbital of porphyrin ring. Thus both [VOP]- and [VOP]＋ can be considered as n-radicals. The ground state of neutral VOP molecule is doublet with the unpaired electron occupying dxy orbital of V atom. In contract to the C4v symmetry of neutral VOP molecule, [VOP]- anion has a ＂rectangular＂ distorted C2v structure due to Jahn-Teller effect. The linear vibronic coupling constants for the Jahn-Teller active modes of [TOP]- were evaluated and the node patterns of frontier KS orbitals are used to explain the reason why the distortion occurs along specific modes. The ground state [VOP]＋ has a porphyrin ring with pronounced bond length alternation due to pseudo-Jahn-Teller effect, causing its symmetry declined from C4v to Ca. The bond length alternation is well explained with the node patterns of re-constructed frontier KS orbitals.

关 键 词：Vanadyl porphyrin Jahn-Teller effect Vibronic coupling 

分 类 号：O342[理学—固体力学] TM262[理学—力学]