The Effects of Finite Length on the Electronic Structure of Carbon Nanotubes
The Effects of Finite Length on the Electronic Structure of Carbon Nanotubes
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DOI：
10.1021/jp983725m
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发表时间：
1998-08
影响因子：
3.3
通讯作者：
A. Rochefort;D. Salahub;P. Avouris
中科院分区：
文献类型：
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作者：
A. Rochefort;D. Salahub;P. Avouris
本文采用从头算和半经验量子计算方法研究了有限长扶手椅型碳纳米管的电子结构。电子沿着管轴的附加限制导致短扶手椅型管中的带隙开放。带隙的值随管长的增加而减小;然而，这种减小不是单调的，而是在短管中显示出明确的振荡。这种振荡可以解释的周期性变化的HOMO和LUMO轨道的管的键合特性。也发现小尺寸的石墨烯片具有有限的带隙，但没有观察到明显的振荡。随着管长的增加，态密度（DOS）谱从零维（0-D）系统的特性演化到离域一维（1-D）系统的特性。对于10 nm长的管，这种转变似乎已经完成。纳米管的化学稳定性，表达…
The electronic structure of finite-length armchair carbon nanotubes has been studied using several ab-initio and semiempirical quantum computational techniques. The additional confinement of the electrons along the tube axis leads to the opening of a band-gap in short armchair tubes. The value of the band-gap decreases with increasing tube length; however, the decrease is not monotonic but shows a well-defined oscillation in short tubes. This oscillation can be explained in terms of periodic changes in the bonding characteristics of the HOMO and LUMO orbitals of the tubes. Finite-size graphene sheets are also found to have a finite band-gap, but no clear oscillation is observed. As the length of the tube increases the density of states (DOS) spectrum evolves from that characteristic of a zero-dimensional (0-D) system to that characteristic of a delocalized one-dimensional (1-D) system. This transformation appears to be complete already for tubes 10 nm long. The chemical stability of the nanotubes, express...