Sm富勒烯的价带光电子能谱  

Valence band photoemission of Sm fullerides

作　　者：王晓雄[1] 李宏年[1] 钱海杰[2] 苏润[2] 钟俊[2] 洪才浩[2] 王嘉欧[2] 

机构地区：[1]浙江大学物理系,杭州310027 [2]中国科学院高能物理研究所,北京100049

出　　处：《物理学报》2006年第8期4265-4270,共6页Acta Physica Sinica

基　　金：北京同步辐射实验室资助的课题.~~

摘　　要：用紫外光电子能谱和同步辐射光电子能谱研究了Sm掺杂C60薄膜的价带电子结构.Sm的价电子大部分转移给C60,化学键以离子性为主.对于任何化学配比都没有观察到费米边,所以Sm富勒烯超导相在室温下为半导体性质.获得了很接近单相Sm2.75C60的样品在费米能级附近的电子态密度分布.固溶相的光电子发射与Sm2.75C60有明显区别.SmxC60(2.75<x<6)样品不是Sm2.75C60和Sm6C60的两相混合,说明有另一个相的存在或者在Sm掺杂过程中电子连续填充LUMO+1能带.不同相之间的界面在130℃以上不稳定.Valence band structure of Sm-intercalated Coo thin films is researched with ultraviolet photoelectron spectroscopy and synchrotron-radiation photoemission spectroscopy. Most valence electrons of Sm transfer to C60, and the bonding nature is mainly ionic. No Fermi edge is observed for all stoichiometries. Thus the superconducting Sm fulleride has semiconducting property at room temperature. Density of states near the Fermi level is obtained for single phase of Sm2.75 C60 Photoemission of the solid solution phase differs apparently from that of Sm2.75Coo. SmxC6o（2.75 〈 x 〈 6） is not the mixture of phase-separated Sm2.75 C60 and Sm660, which indicates that another phase exists or Sm doping proceeds smoothly through the LUMO ＋ 1 band. The interfaces between different phases are unstable above 130℃.

关 键 词：C60的Sm填隙化合物 价带光电子能谱 电子结构 

分 类 号：TN201[电子电信—物理电子学]