黄春林,段海明

• 1:新疆大学物理科学与技术学院

摘要(Abstract)：

用密度泛函理论研究了小团簇Fe_nCo和Fe_nNi(n≤5)的基态几何结构、电子特性和磁性.发现Fe_4Ni团簇具有幻数结构,而对于Fe_nCo团簇没有发现幻数结构.所有这些团簇呈铁磁性而且其自旋磁矩都大于对应块体的磁矩.一般认为团簇的磁矩受几何结构影响很大,然而这些小团簇的自旋磁矩对结构不敏感,我们认为出现这种奇特现象的主要原因是当结构变化时自旋向上和自旋向下的最高占据态对应能级高低序列保持不变.

关键词(KeyWords)： 密度泛函理论;团簇;磁性

Abstract:

Keywords:

基金项目(Foundation): Supported by the National Natural Science Foundation of China(Grant No.10347010,10864005);; the Scientific Research Starting Foundation for Returned Overseas Chinese Scholars,Ministry of Education,China

作者(Author): 黄春林,段海明

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