Ab initio Molecular Dynamics Study on Small Carbon Nanotubes

作     者：YE Lin-Hui LIU Bang-Gui WANG Ding-Sheng 叶林晖;刘邦贵;王鼎盛

作者机构：Institute of Physics and Center for Condensed Matter PhysicsChinese Academy of Science P.O.Box 603Beijing 100080 Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100080 

出 版 物：《Chinese Physics Letters》 (中国物理快报（英文版）)

年 卷 期：2001年第18卷第11期

页      面：1496-1499页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：Supported by the National Key Projects of Basis Research under Grant Nos.G1999064509 and G1999032801 Chinese Academy of Sciences under Grant No.KJCX2-W5-1 

主　　题：Small Molecular curvature 

摘      要：Ab initio molecular dynamics simulations are performed on small single wall nanotubes. By structural relaxation,the equilibrium C-C bond lengths and bond angles are determined. Our result shows that for both zigzag and armchair nanotubes there are two nonequivalent bond lengths. One bond stretches from that of the graphene sheet, while the other shrinks. Small variations on bond angles are also shown. Energy bands are calculated for the optimized structures. It is found that the intrinsic curvature of the very small nanotube greatly modifies the energy band which can no longer be well described in the tight-binding zone-folding picture. In our calculation very small nanotubes are metallic. The energy per atom fits quite well with the relation of E(R) = E0 + f/R2 even for the extreme small radius. The implications of the results on the properties of small nanotubes are discussed.