(LiH)_(n)(n=1~5)团簇与NH_(3)反应的密度泛函理论研究  

Density functional theory study on the reaction between(LiH)_(n)(n=1~5) clusters and NH_(3)

作　　者：董肖 DONG Xiao(Xinjiang Laboratory of Phase Transitions and Microstructures in Condensed Matter Physics,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》2021年第1期70-76,共7页Journal of Atomic and Molecular Physics

基　　金：新疆维吾尔自治区高校科研计划项目(XJEDU2017S050)。

摘　　要：采用密度泛函理论中杂化密度泛函B3LYP/6-311G(d,p)方法,对(LiH)_(n)(n=1~5)团簇结构进行计算,得到最稳定构型,并计算分析其与NH_(3)的反应机理.对各反应的中间体和过渡态进行频率分析和内禀反应坐标(IRC)计算,以验证反应的正确性.用QCISD/6-311G(d,p)方法计算各驻点的单点能,得到能量信息.结果表明:各反应所释放H2中的两个氢原子分别来源于NH_(3)和(LiH)_(n)(n=1~5)团簇.弱化N-H键的作用有利于反应能垒的降低,是反应脱氢的关键.LiH团簇尺寸变化对反应能垒没有太大影响.Geometrical structures of(LiH)_(n)(n = 1 ~ 5) clusters and the reaction mechanism with NH_(3) have been investigated by a B3LYP method of density functional theory at the 6-311 G(d,p) level. Vibration analysis and intrinsic reaction coordinates(IRC) calculation at the same level have been applied to validate the connection of the stationary points. The single point energy of each station point is calculated using the QCISD method at the 6-311 G(d,p) level to get the energy information. The results indicate that the two released hydrogen atoms in H2 come respectively from NH_(3) and(LiH)_(n)(n = 1 ~ 5) clusters in the reactions. The sticking point of the dehydrogenation is overcome to break the bond of N-H,weakening the N-H bond is beneficial to the reaction. The size change of LiH cluster does not have much influence on the reaction energy barrier.

关 键 词：密度泛函理论 (LiH)_(n)(n=15)团簇 过渡态 

分 类 号：O643.12[理学—物理化学]