金属氢化物中质子耦合电子转移反应的理论研究  

Theoretical Study of Proton-Coupled Electron Transfer Reaction in MetalHydride Complexes

作　　者：刘晓云 但晓寒 史强[1,2] Xiaoyun Liu;Xiaohan Dan;Qiang Shi(Beijing National Laboratory for Molecular Sciences,State Key Laboratory for Structural Chemistry of Unstable and Stable Species,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院化学研究所,分子动态与稳态结构国家重点实验室,北京分子科学国家研究中心,北京100190 [2]中国科学院大学,北京100049

出　　处：《Chinese Journal of Chemical Physics》2024年第2期199-210,I0102,共13页化学物理学报（英文）

基　　金：This work is supported by the National Natural Science Foudation of China(No.21933011);the K.C.Wong Education Foundation.

摘　　要：金属-氢配合物在多种催化反应中起着重要作用最近的研究表明,与吡啶基团共价连接的钨氢配合物可以发生协同的质子耦合电子转移反应.本文使用密度泛函理论和非绝热速率理论研究了该类弱氢键体系中的协同质子耦合电子转移反应.首先通过密度泛函理论构建了金属-氢配合物质子自由度的二维势能面.然后求解薛定方程得到了波函数和振动能级,并用于分析各对振动态之间的跃迁速率和总的速率常数.结果表明,由于质子给体-受体之间距离的热涨落,即使在质子给体和受体之间仅存在弱氢键的情况下,协同质子耦合电子转移反应和总反应速率常数也可以得到显著增强.Metal-hydride(M-H)complexes are crucial for a variety of catalytic reactions.There have been indications of concerted proton-coupled electron transfer(PCET)reaction recently in several studies involving tungsten hydride complexes covalently connected to pyridyl groups.In this piece of work,we use the density functional theory and nonadiabatic rate theory to study concerted PCET reactions in weakly hydrogen bonded systems.Two dimensional potential energy surfaces of the metal-hydride complexes are first constructed.Wave functions and vibrational energy levels are then obtained,which are used to analyze the transition between each pair of vibronic states and to obtain the total rate constant.It is demonstrated that,because of the hydrogen donor-acceptor distance thermal fluctuations,the concerted PCET reaction and the total reaction rate constant can be significantly enhanced even in the case of weak hydrogen bonding between the proton donor and acceptor.

关 键 词：质子耦合电子转移 速率常数 密度泛函理论计算 非绝热 跃迁 

分 类 号：O64[理学—物理化学]