第I类硅笼中M@Si_(20)原子团的电子态研究  

Study on electronic properties of M@Si_(20) clusters in type-I silicon clathrates

作　　者：刘洋[1] 陈宁[1] 李阳[1] 曹国辉[1] 

机构地区：[1]北京科技大学材料物理系,北京100083

出　　处：《功能材料与器件学报》2004年第3期337-342,共6页Journal of Functional Materials and Devices

基　　金：国家自然科学基金资助项目(No.50372005)

摘　　要：采用量子化学SCF-Xα-SW方法计算了第I类Si基笼状化合物中M@Si20(M=□,Na,Zr,Cs,Ba,Ce)原子团的态密度,及各体系中Si原子的结合势。结果表明在原子团M@Si20中笼内金属原子M与笼上硅原子间的结合强度随金属原子不同而变化,结合方式依赖于金属原子M的电子结构。笼内原子的d轨道主要分布在完整晶体的导带底,此外另有少部分与价带结合。作为新型硅笼材料设计,探讨了构成笼内含Ce、Zr的硅笼材料的可能性。A series of clusters, M@Si20(M=vacancy, Na,Ba,Zr,Cs,Ce), in silicon based clathrate compounds are calculated using SCF-Xα-SW method to investigate the combination between Si20 cage and the inside metal atom M. Local density of electronic state of these clusters shows that d orbitsof the guest atoms make considerable contribution to p-like segment of the valence band that mainlyformed by the Si20 cage, which implies the coupling between guest atom and the cage exists not only inthe conduction band, but also in the valence band. Synthesis of Ce, Zr doped type-I clathrate com-pounds is possible.

关 键 词：IV族元素 第Ⅰ类硅笼 SCF-Xα-SW方法 电子态密度 电荷转移 

分 类 号：TN304.12[电子电信—物理电子学]