氢卟啉,氯取代卟啉结构和吸收光谱性质的理论研究

Theoretical Study on the Structure and Absorption Spectrum Properties of porphyrins and Chloroporphyrins

卟啉及其衍生物因其优良的光电性能在许多领域得到了广泛应用。利用密度泛函理论(DFT)研究了卟啉(FBP)、2-氯卟啉(2-Cl-FBP)、4-氯卟啉(4-Cl-FBP)和2'-氯卟啉(2'-Cl-FBP)的四种卟啉类化合物的几何结构和分子轨道能级。采用含时密度泛函理论(TD-DFT)方法计算了四者在气态和溶剂场极化连续模型下的电子吸收光谱。通过对他们在气态和不同溶剂条件下的Soret带和Q带两个特征吸收峰的分析,获得了氯原子位置变化以及不同极性溶剂条件下吸收光谱的递变规律,并通过轨道分析解释了光谱变化原因。

Due to the excellent photoelectric performance, porphyrin and its derivatives have been widely applied in many fields.Applied with the density functional theory(DFT), the geometry and molecular orbital energy levels of free base porphyrin(FBP), 2-chloro-porphyrin(2-Cl-FBP),4-chloro-porphyrin(4-Cl-FBP) and 2’-chloro-porphyrin(2’-Cl-FBP) were investigated.The electronic absorption spectra of these four compounds in the gas and solvent field polarization continuous models were calculated through the time dependent density functional theory(TD-DFT).The characteristic adsorption of Soret band and Q band in the gas state and different solvents were analysed to give the gradation law of the adsorption spectra with the change of the connected position of chlorine atom and the change of solvents.Moreover,the analyses of molecular orbital explain the change of spectra.