(1. 广西大学 物理系, 南宁 530004;
2. 广西师范大学 化学化工系, 桂林 541004)
摘 要: 利用电荷自洽离散变分Xα(SCC-DV-Xα)方法计算了LaNi4M(M=Ni,Cu,Mn, Al)及其氢化物的电子结构,分析了电子结构对吸氢性能的影响。结果表明:LaNi4M氢化物的稳定性与氢原子的电荷转移密切相关,进入H1s轨道的电荷增大,将会降低其稳定性;LaNi4M的循环寿 命与合金中La的4f和Ni(1)的4p轨道间的成键强度有关,杂化成键越强,相应的循环寿命越长;Ni(3)的3d轨道也与La的4f轨道有成键作用,但这种作用在吸氢后被减弱。
关键字: 电子结构;吸氢性能;LaNi4M氢化物
structure of LaNi5 base alloys and
hydrogen absorption properties
(1.Department of Physics, Guangxi University,
Nanning 530004, China;
2.Department of Chemistry and Chemical Engineering,
Guangxi Normal University, Guilin 541004, China)
Abstract:The electronic structures of LaNi4M(M=Ni, Cu, Mn, Al) and their hydrides we re investigated by the SCC-DV-Xα (Self-Consistent-Charge Discrete Variational Xα) method. The results show that the stabilities of LaNi4M hydrides are related to charge transferred to hydrogen atom, which is found to be strengthen by decrease of the transferred charge; the cycle lifetime of LaNi4M is affected by strength of bond between 4f orbit in La atom and 4p orbit in Ni(1) atom, the stronger the bond is, the longer the cycle lifetime is; there is also a orbital action between 3d orbit in Ni(3) atom and 4f orbit in La atom, however the orbital action is weaken when hydride is formed.
Key words: electronic structure; hydrogen absorption properties; LaNi4M hydride