1,8-萘酰亚胺类衍生物的结构及紫外-可见吸收光谱  

Structures and UV-Vis Absorption Spectra of 1,8-Naphthalimide Derivatives

作　　者：齐齐[1] 孙岳明[1] 哈涌泉[1] 

机构地区：[1]东南大学化学化工学院,南京211189

出　　处：《物理化学学报》2009年第6期1143-1148,共6页Acta Physico-Chimica Sinica

基　　金：国家重点基础研究发展计划(973)(2007CB936300)资助项目

摘　　要：用密度泛函方法(DFT)优化了一系列1,8-萘酰亚胺衍生物,用含时密度泛函(TDDFT)和导体极化连续模型(CPCM)计算了它们在气相、环己烷和二氯甲烷溶剂条件下的紫外可见吸收光谱.计算结果表明,优化的几何结构和X射线晶体结构数据吻合较好.萘环4和5位胺基上取代基团(氢基、甲基、苯基和萘基)的变化使得它与萘酰亚胺部分的连接键长(N—C)变长、电荷转移增强、带隙降低.溶剂化显色效应和前线轨道电子云一致表明此类物质的最大吸收峰对应π-π*跃迁.异构体A中的分子内电荷转移增大和带隙的降低是它的紫外吸收光谱最大吸收峰比异构体B的发生红移的主要原因.Ground state geometries of a series of l, 8-naphthalimide derivatives were calculated by density functional theory （DFT）. Their UV-Vis absorption spectra in gaseous, C6H12 （cyclohexane） and CH2Cl2 environments were calculated by the time dependent-DFT （TDDFT） method and the conductor polarizable continuum model-TDDFT （CPCM-TDDFT） method. We found that theoretical values were in good agreement with X-ray geometric parameters. The addition of various substituents （H, methyl, phenyl, and naphthyl） to the 4 and 5 positions of the naphthalic ring＇s amines lengthened the （N--C） bond length between the amine and the naphthalimide moiety. This bond lengthening resulted in more intramolecular charge transfer and a lower energy gap. Both the bathochromic effect and the frontier orbital electron cloud density showed that the absorption maximum corresponds to a π-π＊ transition. By comparison to the maximum absorption peak of UV-Vis absorption spectrum of the B isomer, that of the A isomer was red shifted and this was mainly attributed to more intramolecular charge transfer and a lower energy gap.

关 键 词：1 8-萘酰亚胺衍生物 密度泛函理论 吸收光谱 

分 类 号：O625.6[理学—有机化学]