甲基定位效应的密度泛函理论研究  

Density functional theory study on the orientation effect of methyl

作　　者：陈海群[1] 赵银芝[1] 赵国栋[1] 孙小强[1] 

机构地区：[1]江苏工业学院江苏省精细化工重点实验室,江苏常州213164

出　　处：《计算机与应用化学》2008年第6期693-696,共4页Computers and Applied Chemistry

基　　金：国家自然科学基金(50372028);江苏省政府留学奖学金资助.

摘　　要：以苯、甲苯及甲苯氯化反应所形成的σ络合物(中间体)为研究对象,运用密度泛函理论的B3LYP法,在6-311G^(DK2|**)水平上优化计算,并寻找σ络合物相互转化的过渡态。算出苯和甲苯的电荷分布、σ络合物的能量与电荷分布,以及σ络合物之间相互转化的过渡态的结构参数和能量。从电荷密度、σ络合物的稳定性及其相互转化机理3个方面,解释甲基的邻、对位的定位效应。为进一步研究取代基的定位效应,提供一些理论依据。All geometries which included benzene, toluene, σ-complexes and transition states（TS） obtained from inter-transfer of σ- complexes were fully optimized by Becke＇ s hybrid functional, B3LYP, at 6-311 G ＊＊ level, according to density function theory（DFT）. On the basis of these structures, the charges of them were computed. Meanwhile, the energies of different σ-complexes and TS were calculated and the structural parameters of TS were also obtained. The orientation effect of methyl was studied by analyzing charge density, the stability of different σ-eomplexes and the inter-transfer pathway of σ-complexes. Some clues in theory were given for further study of orientation effect.

关 键 词：密度泛函理论 定位效应 电荷密度 σ络合物 过渡态 

分 类 号：O621.11[理学—有机化学] O641.12[理学—化学]