摘要
采用基于密度泛函理论的从头算对bcc和fcc过渡金属中氦原子的稳定性进行了研究。计算结果表明,除了V和Nb外,不管是bcc还是fcc,氦都是在替换位置最稳定。对于间隙位置,在bcc过渡金属中,氦在四面体位置比八面体位置更稳定,而在fcc过渡金属中,间隙氦的稳定位置没有规律可循。对有磁性的bccFe和fccNi进行自旋和非自旋极化研究,发现金属的磁性对间隙氦的稳定位置没有直接的影响。
The relative stability of single He defect in bcc and fcc metals is investigated using ab initio calculations based on density functional theory （DFT）. The calculations reveal that for all metals involved, except for V and Nb, the substitutional position is the most stable. Furthermore, the tetrahedral site is energetically more favorable for the He interstitial than the octahedral site in the bee metals, but the relative stability of He defects in the fee metals is not definitive. The He formation energies in bee Fe and fee Ni at the tetrahedral and octahedral sites with or without spin polarization are investigated. It is interesting to find that the magnetism of host atoms does not directly affect the relative stabilities of He interstitial sites.
出处
《电子科技大学学报》
EI
CAS
CSCD
北大核心
2008年第4期558-560,共3页
Journal of University of Electronic Science and Technology of China
基金
教育部“新世纪优秀人才支持计划”(NCET-04-0899)
