基于密度泛函理论对咔咯-吩噻嗪二元体激发态电荷转移的研究

A Study of the Excited-State Charge Transfer of Corrole-Phenothiazine Dyads Based on the Density Functional Theory

采用密度泛函理论(DFT)对咔咯与吩噻嗪形成的F10C-PTZ供体-受体体系进行了计算,包括几何结构、前线分子轨道、电子-空穴分析、吸收光谱等基态和激发态性质;探讨了二元体间隔基和取代基位置对电荷转移激发态的影响.结果表明:F10C-PTZ二元体存在供体-受体间的电荷转移激发态;间隔基的C—C键会阻碍供体-受体的电荷转移,而间隔基的C C键可增强体系的共轭性,有利于供体-受体的电荷转移;当供体取代位置与五氟苯基相邻时,咔咯上五氟苯基的拉电子效应使得供体-受体激发的电荷转移更易于发生.

The density functional theory(DFT)was used to investigate the ground-state and excited-state properties,including optimized geometry,frontier molecular orbital,electron-hole distribution and absorption spectra of the donor-acceptor systems formed by corrole and phenothiazine(F10C-PTZ).The effect of spacer and substituent position on charge transfer excitation was discussed in detail.The results showed that in the F10C-PTZ dyads exist excited states of charge transfer characterized by donor(PTZ)and acceptor(corrole)features.Carbon-carbon single bond of the spacer will hinder donor-acceptor charge transfer,while carbon-carbon double bond in spacer will enhance the conjugation of the system and facilitate donor-acceptor excitation charge transfer.When the donor group PTZ is in close to the pentafluorophenyl group on corrole ring,it will also promote the donor-acceptor excitation charge transfer.