Mg_2Ni合金及其氢化物的电子结构及成键特性的第一原理计算  

First principles calculation on Mg_2Ni alloy and its hydride electronic structure and bond characteristics

作　　者：马树元[1] 黄丹[1] 郑定山[1] 肖荣军[1] 郭进[1] 

机构地区：[1]广西大学物理科学与工程技术学院,南宁530004

出　　处：《中国有色金属学报》2007年第1期118-123,共6页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(50561002);教育部科研重点基金资助项目(03104);广西大学科研重点资助项目(2004ZD04)

摘　　要：采用第一原理方法对Mg2Ni及其氢化物电子结构进行计算。计算结果表明:在Mg2Ni合金中,原子间的相互作用主要发生在Ni原子层附近,而沿c轴方向Mg原子与Ni1、Ni2原子相互作用很弱,沿着a、b轴原子间的相互作用强于沿c轴的相互作用;在Mg2Ni氢化物中,Ni原子轨道与H原子轨道在成键区存在较强的s-p-d杂化作用;Mg2Ni合金氢化物在LT→HT的转变中,Mg与NiH4的离子相互作用减弱是造成合金氢化物的稳定性下降的一个原因。The electronic structures of hydrogen storage alloy, Mg2Ni, and its hydride were investigated by the first principles method. It is found that the interactions among atoms are mainly around the Ni atom plane. Along the c axis weak interactions occur among Mg-Ni 1 and Mg-Ni2. The interactions along a and b axis are stronger than that along c axis in Mg2Ni alloy. Strong s-p-d hybridization exists between Ni and H in Ni-H bonding area in Mg2NiH4 compound. During the LT→HT phase transformation, the strength of ionic interaction between Mg and NiH4 is weakened, which is a reason why the stability of alloy hydride decreases.

关 键 词：MG2NI MG2NIH4 电子结构 成键特性 

分 类 号：TG23[金属学及工艺—铸造]