理论研究吖啶-9-氨基亚甲基丙二酸二乙酯的吸收与发射光谱性质  

A Theoretical Study of the Properties of Absorption and Emission Spectra of Diethyl [(Acridinium-9-Ylamino)Methylene] Malonate

作　　者：王辉[1] 何荣幸[1] 申伟[1] 李明[1] 

机构地区：[1]西南大学化学化工学院,重庆400715

出　　处：《西南大学学报（自然科学版）》2008年第5期73-80,共8页Journal of Southwest University(Natural Science Edition)

基　　金：教育部科学技术重点资助项目(NO104263)

摘　　要：基于9-氨基吖啶(9AA)和吖啶-9-氨基亚甲基丙二酸二乙酯(9AADMM)基态和第一单重激发态的结构优化,利用密度泛函理论考察了它们在气相和液相中的吸收和发射光谱性质,解释了两者具有不同光谱特征的原因.结果表明,9AA与9AADMM第一激发态都是具有ππ*性质的局域激发态;9AADMM第二、三激发态是有ππ*性质的电荷转移态;吸电子基团的引入是导致9AADMM产生两个强吸收峰的根本原因.根据广义的Mulliken-Hush公式,计算了9AADMM基态与激发态的电子转移耦合矩阵元,预测了体系的两个强吸收分别来源于S1态和能量简并的S2、S3态.Based on the optimized structure of 9-aminoacridine and diethyl [（acridinium-9-ylamino） methylene] malonate （9AADMM）, we examine the properties of the absorption and emission spectra of the 9AADMM system in gas and liquid solvent based on the density functional theory and explain the causes for the different properties of the two compounds. The results prove that the excitation states of both 9AA and AADEM are local excitations which are characterized by ππ＊ ; that the second and third excitation states of 9AADMM are charge-transfer states characterized by ππ＊ ; and that it is the introduction of elec- tron withdrawing group that causes the two strong absorption peaks of 9AADMM. According to the generalized Mulliken-Hush formula, we calculate the electronic coupling matrix elements of 9-AADMM at both ground and excitation states and predict that the two strong absorptions of the system are respectively from Sistate and energy-degenerated S2, S3 states.

关 键 词：密度泛函理论 激发态 吸收和发射光谱 光谱性质 耦合矩阵元 

分 类 号：O621[理学—有机化学]