METALLIC PHASE AND INSULATING CHARACTER OF ALKALI-EARTH METAL DOPED C60①  

作　　者：曹阳 陈良进 陈波 冯建文 陈文建 

机构地区：[1]Chemstry Department [2]Chemistry Department,Yangzhou Universtry,Yangzhou

出　　处：《苏州大学学报（自然科学版）》1995年第2期78-85,共8页Journal of Soochow University(Natural Science Edition)

摘　　要：The three dimensional EHMO crystal orbital calculations for crystalline Ba6 C60,Ca3 C60 and Ca5 C60 are reported.The ground state of partially doped Ca3 C60 is found to be insulating with an indrect energy gap of 0.5eV.In contrast,the Ca5 C60 forms a metallic conducting phase with a set of three half-filled bands crossing the Fermi level which is Found to locate close to a peak of the density of state. The character of crystal orbitals near the Fermilevel for both Ca3 C60 and Ca5 C60 is completely carbon-like.In both cases the Ca3 atoms are almost fully ionized and C60 molecules form a stable negative charge state with six to ten additional electrons.The conductivity of Ba6 C60 is resuted from the incomplete charge tranfer.The valance charge of every Ba ion is about 0.33.The total charge tranfer of six Ba atoms is almost the same as that of five Ca atoms.The three dimensional EHMO crystal orbital calculations for crystalline Ba6 C60,Ca3 C60 and Ca5 C60 are reported. The ground state of partially doped Ca3 C60 is found to be insulating with an indirect energy gap of 0. 5eV. In contrast, the. Cas C60 forms a metallic conducting phase with a set of three half - filled bands crossing the Fermi level which is Found to locate close to a peak of the density of state. The character of crystal orbitals near the Fermilevel for both Ca3 C60 and Ca5 C60 is completely carbon - like. In both cases the Ca3 atoms are almost fully ionized and C60 molecules form a stable negative, charge state with six to ten additional electrons. The conductivity of Ba6 C60 is resute.4 from the incomplete charge tranfer. The valance charge of every Ba ion is about 0. 33. The total charge tranfer of six Ba atoms is almost the same as that of five Ca atoms.

关 键 词：碱性土壤金属 碳 绝缘性 金属相 超导体 C60 EHMO 

分 类 号：TM26[一般工业技术—材料科学与工程]