一类有机发色团分子电子吸收跃迁能的计算研究

Theoretical study on the electronic transition energies of a series of organic chromophores

利用MINDO／3、MNDO、AM1以及PM3四种通用半经验量子化学计算方法和限制性多电子组态相互作用方法(MECI)并根据Onsager方程计算溶剂效应,成功地对9-氨基吖啶(AMAR)、9,10-二甲氧基-2-甲基蒽(DMAN)、9-甲基蒽(AN)、α-萘甲酸乙酯(NAAC)四种有机发色团分子的吸收跃迁能进行了理论计算,吸收跃迁能理论计算值与光谱实验测定值相关分析表明,它们具有相当好的相关系数,显示半经验量子化学方法可以作为预测有机发色团光谱性质的有效计算方法。

By using MINDO/3, MNDO, AMI and PM3 semiempirical quantum chemistry methods together with limited multi-electron configuration interaction method (MECI) and also considering the effect of solvents calculated by Onsager equation, the transition energies of four chromophores 9-aminoacridine (AMAR), 9,10-dimethoxy-2-methylanthracene (DMAN), 9-methylantheracene (AN), α-naphthate ethyl NAAC) were successfully calculated at the first time. It was found that the correlation coefficients (R) of regressive expressions (Eobs = A + B X Ecalc) between the calculated energies and observed ones were good. It also shows that the prediction of the absorption spectrum by current semiempirical quantum chemistry method is feasible.