有限长锯齿型碳纳米管的电子结构与管径效应

Electronic Structures and the Tubular Radius Effects of Zigzag Carbon Nanotubes with Finite Size

在B3LYP/6-31G//PM3水平上对一系列有限长锯齿型碳纳米管(n,0)(n=6～11)的构型和电子结构进行了研究.结果表明,最高占据轨道(HOMO)与最低空轨道(LUMO)间的能隙(Eg)随着管径的增大出现随奇偶n值的振荡变化,随着管长的增加呈单调减小的趋势;前线轨道波函数的成键结构随管径的变化而变化,但并不随管长的变化而改变,HOMO的成键性质与几何结构之间存在对应关系.

The geometries and wave-function of the frontier orbitals for a series of finite zigzag carbon anotubes (n, 0) (n = 6similar to11) were studied at B3LYP/6-31G//PM3 level. The results indicate that the energy gap between the HOMO and LUMO exhibits oscillation with the number odd-even n as the tubular radius increases, and the energy gap has a monotonously decreasing trend with the increase of the tubular length. The structure for wave-function of the frontier orbitals depends only on the tubular radius, irrespective with the tubular length. The bonding characteristic of the HOMO orbital has corresponding relation with the geometric structure.