摘要
采用密度泛函理论B3LYP方法研究了NH_3与MgH_2的放氢反应机理,在6-311G(d,p)基组水平上对反应物、中间体、过渡态及产物进行了全几何参数优化.频率分析和内禀反应坐标(IRC)计算证实了中间体和过渡态的正确性和相互连接关系.计算结果表明:反应分两步单通道的氢取代过程,且反应过程相类似,反应生成Mg(NH_2)_2和2H_2.两步氢取代反应所释放的H_2中两个H原子分别来源于NH_3和MgH_2.反应脱氢的关键在于克服N—H键断裂所需能量.
The reaction mechanism between NH3 and MgH2 has been investigated by a B3 LYP method of density functional theory,and the geometries and harmonic vibration frequencies of reactants,intermediates,transition states and products have been calculated at the B3 LYP /6-311G（ 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 results indicate that the reaction between NH3 and MgH2 has two single-channel hydrogen substitution reactions,the reaction products are Mg（ NH2）2 and H2.The two released hydrogen atoms in H2 come from NH3 and Mg H2,respectively.The sticking point of the dehydrogenation is overcome to break the bond of N-H.
出处
《原子与分子物理学报》
CAS
CSCD
北大核心
2016年第5期801-806,共6页
Journal of Atomic and Molecular Physics
基金
伊犁师范学院一般项目(2015YSYB28)
关键词
密度泛函理论
NH3
过渡态
反应机理
Density functional theory
NH3
Transition states
Reaction mechanism
