Theoretical analysis of β-LaNi_5H_x (5≤x≤8):structure and energetics  

作　　者：刘杨 吴锋 

机构地区：[1]National Development Center of Hi-Tech Green Materials, Beijing Institute of Technology,Beijing 100081, China

出　　处：《中国有色金属学会会刊：英文版》2005年第5期1031-1039,共9页Transactions of Nonferrous Metals Society of China

基　　金：Project(2001CCA05000)supportedbytheNationalKeyProgramforBasicResearch;Project(2002CB211800)supportedbytheNationalBasicResearchandDevelopmentProgramofChina

摘　　要：The calculations of total energy, band structure, and electronic density of states and Mulliken population analysis of β-LaNi5Hx（5≤x≤8） were performed by adopting the method of total energy based on the density functional theory. The augmented plane wave function was selected as the basis set in combination with ultra-soft pseudo-potential technology. The influence of the amount of H absorbed in alloys was discussed in terms of geometry, electronic structure and thermodynamic derived from calculated results. The results show that the amount of H absorbed and the preferred site occupation of the absorbed hydrogen atoms were controlled by the position of H-bands and the energy gap between H-bands and conduction bands. The β-phase hydrides of LaNi5 are most stable when hydrogen atom capacity coating in the range of 67.The calculations of total energy, band structure, and electronic density of states and Mulliken population analysis of β-LaNi5Hx（5≤x≤8） were performed by adopting the method of total energy based on the density functional theory. The augmented plane wave function was selected as the basis set in combination with ultra-soft pseudo-potential technology. The influence of the amount of H absorbed in alloys was discussed in terms of geometry, electronic structure and thermodynamic derived from calculated results. The results show that the amount of H absorbed and the preferred site occupation of the absorbed hydrogen atoms were controlled by the position of H- bands and the energy gap between H-bands and conduction bands. The β-phase hydrides of LaNi5 are most stable when hydrogen atom capacity coating in the range of 6 ～ 7.

关 键 词：LANI5合金 氢化物 几何学 电子结构 热处理 金属热力学 

分 类 号：TG111[金属学及工艺—物理冶金]