^(6,7)LiX(X=H,D,T)+H_2O潮解反应过程中氢同位素效应:量子化学研究（英文）  

H Isotope Effects in ^(6,7)LiX(X=H,D,T)+H_2O Deliquescence Reactions:a Quantum Chemistry Study

作　　者：李如松 刘志勇 辛督强[1] 王震[1] Li Rusong;Liu Zhiyong;Xin Duqiang;Wang Zhen(Xijing University, Xi＇an 710123, China;Beijing Research Institute of High Technology, Beijing 100084, China)

机构地区：[1]西京学院,陕西西安710123 [2]北京高新技术研究所,北京100084

出　　处：《稀有金属材料与工程》2018年第6期1662-1667,共6页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China(51401237,51271198,11474358);Defence Foundation of China([2014]689,2015ZZDJJ02,2014QNJJ018,YX2012cxpy06)

摘　　要：采用二阶微扰方法 MP2对LiD/LiH/LiT+H_2O反应机制进行理论,计算获得的焓变化和反应速率常数与实验数据和其他理论值一致。结果表明:LiD+H_2O反应存在2个反应通道,通道一的反应势垒仅为9.31 kJ/mol,并且通道一是主要的反应通道。平衡同位素效应EIE和动力学同位素效应KIE计算结果表明:虽然反应中同位素化学键发生破裂,属于主级同位素效应,但是动力学同位素效应不是非常明显,这与主级同位素效应的理论极大值不同。在动力学同位素效应的贡献中η_(vib)>η_(rot)>η_(tun)>η_(pot)>η_(trans),这表明同位素效应的主要贡献来自振动因子,发生同位素效应替代后,与之相关的振动模式的振动频率明显降低,引起KIE的变化。We performed theoretical investigation on mechanisms of LiD/LiH/LiT ＋H2O reactions with second order perturbation theory（MP2）. Calculations of enthalpy change and reaction rate constant are in agreement with experimental data and other theoretical values. Results show that two reaction channels exist for LiD ＋ H2O reaction, and channel 1 is the main reaction channel. Kinetic Isotope Effect（KIE） is not so large although fracture of isotope bond takes place in the reaction, which is noticeably different from theoretical maximums of primary isotope effect. Individual contributions of KIE effect are listed as follows ηvib〉ηrot〉 ηtun 〉ηpot 〉ηtrans, indicating that main contribution of isotope effect results from vibration factor.

关 键 词：同位素效应 反应通道 振动频率 过渡态 反应速率 

分 类 号：O641.121[理学—物理化学]