MLi_(2)H_(3)(M=Na,K)与NH_(3)反应的密度泛函理论研究  

Density functional theory study on the reaction between MLi_(2)H_(3)(M=Na,K)and NH_(3)

作　　者：董肖 DONG Xiao(Xinjiang Laboratory of Phase Transitions and Microstructures in Condensed Matters,College of Physical Science and Technology,Yili Normal University,Yining 835000,China)

机构地区：[1]伊犁师范大学物理科学与技术学院新疆凝聚态相变与微结构实验室,伊宁835000

出　　处：《原子与分子物理学报》2023年第4期28-34,共7页Journal of Atomic and Molecular Physics

基　　金：伊犁师范大学科研项目(2021YSYB102);新疆维吾尔自治区高校科研计划项目(XJEDU2017S050)。

摘　　要：采用杂化密度泛函方法,对MLi_(2)H_(3)(M=Na,K)团簇与NH_(3)的反应机理进行计算分析,对反应中各驻点几何构型进行优化,经频率分析和内禀反应坐标计算以确证各驻点的正确性和连接关系.经单点能校正计算,给出反应相关的能量信息.结果表明:引入Na和K原子后,反应物LOMO轨道有大幅度的向Na、K原子处的转移.KLi_(2)H_(3)有较小的能隙和电离势及较高的费米能,有较高反应活性.Na、K元素的引入,能破坏反应物的稳定性,降低反应能垒.The reaction mechanism between MLi_(2)H_(3)(M=Na,K)clusters and NH_(3)has been investigated by a B3 LYP method of density functional theory.The geometric configuration of each stationary point in the reaction has been optimized,and the vibration analysis and intrinsic reaction coordinates calculation have been applied to validate the connection of the stationary points.The single point energy of each stationary point is calculated to get the energy information.The results indicate that frontier molecular orbital LUMO has a large transfer to Na/K atoms,after introducing Na and K atoms.KLi_(2)H_(3)has smaller energy gap,smaller ionization potential and higher Fermi energy,and hence has higher reaction activity.The introduction of Na and K elements can destroy the stability of reactants and reduce the reaction energy barrier.

关 键 词：储氢材料 碱金属氢化物 过渡态 

分 类 号：O641[理学—物理化学]