HCN→HNC异构化反应过渡态附近的拓扑特性  

THE TOPOLOGICAL CHARACTERISTICS OF THE STRUCTURES IN THE VICINITY OF TRANSITION STATE OF HCN→HNC ISOMERIZATION

作　　者：李庆明[1] 傅孝愿[1] 张敬畅[2] 曹维良[2] 

机构地区：[1]北京师范大学化学系,北京100875 [2]北京化工学院应化系

出　　处：《物理化学学报》1992年第6期724-727,共4页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金;国家教委博士点基金

摘　　要：电荷密度拓扑分析方法(topological analysis of charge distribution)已经被广泛应用于研究化合物的各种静态性质及反应特性.对IRC反应途径上过渡态附近构型的拓扑性质研究报导较少.本工作是用电荷密度分布的拓扑分析方法对HCN→HNC异构化反应IRC过渡态附近的性质进行了研究.对电荷密度分布拓扑分析和IRC途径确定选用相同的基组,得到了一些新的结论。In this paper,thermal isomerization of HCN to isocyanide HNC has been studied.The topological properties of the structures of some points on IRC path in the vici-nity of transition state have been analyzed. It is found that the transition state forHCN→HNC isomerization reaction is a bond switching point on IRC path in view ofits topological properties. It is a point wherc the 'old' chemical bond H--C beginsto break and a 'new' bond between H atom and the bond critical point of CN beginsto form and this state lasts for a period about ΔS=0.3 (from S=0.00 to S=0.30)on the IRC path. The changes of other properties along the IRC reaction path hasalso been discussed. Together with the reverse reaction, it is realized that the changing of topolo-gical properties of structures in the vicinity of transition state on IRC path is dif-ferent for exothermal and endothermal reactions.

关 键 词：过渡态 HCN 异构化反应 氢化氰 

分 类 号：O622.6[理学—有机化学]