BrO与CH_3SH反应机理的量子化学及拓扑研究  

Quantum Chemical and Topological Study on the Reaction Mechanism of BrO with CH_3SH

作　　者：樊红敏[1] 李晓艳[1] 孟令鹏[1] 郑世钧[1] 曾艳丽[1] 

机构地区：[1]河北师范大学计算量子化学研究所

出　　处：《化学学报》2007年第5期395-402,共8页Acta Chimica Sinica

基　　金：国家自然科学基金(No.20573032);河北省自然科学基金(No.B2006000137);河北师范大学科研基金(No.L2005Q07)资助项目.

摘　　要：利用密度泛函和电子密度拓扑分析方法对BrO与CH3SH反应的微观机理进行了理论研究.在B3LYP/6-311G(d,p)水平上对反应势能面上的各驻点进行几何构型的全优化;振动分析和IRC计算证实了中间体和过渡态的真实性和相互连接关系;计算得到了各反应通道的活化能,并进行了零点能校正.计算结果表明:该反应存在7个反应通道,其中生成CH3S+HOBr和CH3SO+HBr的通道为主要反应通道.通过对反应过程中部分驻点的电子密度拓扑分析,首次发现了接近平面的四元环状过渡态,从而拓展了原来对环状结构过渡态定义的适用范围.The reaction mechanism of BrO with CH3SH has been investigated by density function theory （DFT） and electronic density topological analysis method. Geometries of the stationary points on the potential energy surface have been optimized at B3LYP/6-31 lg （d, p） level. Vibration analysis and intrinsic reaction coordinate （IRC） calculation at the same level have been applied to validate the connection of the stationary points. The reaction barriers with zero point energy correction have also been calculated. The calculated results show that there are seven pathways on the reaction surface of BrO with CH3SH, and those in the formations of CH3S＋HOBr and CH3SO＋HBr are dominant. The non-planar four-member-ring structure transition state （STS）, which was firstly found in this paper, extended the concept of ring STS.

关 键 词：反应机理 电子密度拓扑分析 结构过渡态 

分 类 号：O643.12[理学—物理化学]