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由全碳组成的笼状簇合物(fullerene富勒烯)是不同于石墨,金刚石的碳的新的形态.其中具有截角正20面体结构的C_(60)是在合成富勒烯中采率最高的一种.采用不同的方法分析和计算,C_(60)固体(指FCC结构)的禁带宽度不相同,其值在2.6—1.5eV之间.对于C_(60)分子,采用LDA方法计算HOMO(最高填充分子轨道)同LUMO(最低空分子轨道)间能隙为1.9eV,采用SSH模型计算为1.7eV.群论分析表明其价带(即HOMO)属于h_u群,导带(即LUMO)属于t_(iu)群.由于t_(iu)同h_u的直积不包含t_(iu),所以C_(60)的带间(LUMO-HOMO)为禁
Caryon-like clusters (fullerene fullerenes), which are made of all-carbon, are new forms of carbon different from graphite and diamond. Among them, C 60 with a truncated octahedron structure is used in the synthesis of fullerenes The highest one was obtained.Using different methods to analyze and calculate, the forbidden band width of C_ (60) solid (referring to the FCC structure) is different and its value is between 2.6-1.5eV.For the C_ (60) molecule, LDA The energy gap between HOMO (highest filled molecular orbital) and LUMO (lowest molecular orbital) is calculated to be 1.9 eV and 1.7 eV by SSH model. The group theory shows that the valence band (HOMO) belongs to the h_u group and the conduction band (LUMO) belongs to t_ (iu) group. Since the direct product of t_ (iu) and h_u does not contain t_ (iu), the band of C_ (60)