范德华力对双壁碳纳米管轴向压缩屈曲行为的影响

使用分子动力学方法研究几种不同半径尺寸的单壁碳纳米管组成的双壁碳管，预测了其初始稳定构型；分析了其自由弛豫阶段的特征；并模拟了它们在轴向压缩载荷作用下的屈曲行为；研究了不同层间距导致的范德华力变化对屈曲行为的影响.采用Tersoff-Brenner势描述单壁碳纳米管内原子间作用，Lennard-Jones势描述内外层间的范德华相互作用.计算结果表明：在通常意义下的双壁管间距(约0.34 nm)外还可以存在稳定的双壁碳管构型，并且这些新的稳定构型表现出了不同的力学性质. 关键词： 双壁碳纳米管 分子动力学 屈曲

Influence of van der Waals force on the buckling of double-walled carbon nanotubes

Several novel double-walled carbon nanotubes (DWCNT) composed of different internal and external nanotubes with different diameters are presented and studied by molecular dynamics simulation (MD). Initial equilibrium configurations and characteristics during free relaxation are examined. Buckling of these DWCNTs under axial compression are simulated to examine the influence of van der Waals force on mechanical properties of DWCNTs. The interaction of atoms in each wall and the van der Waals force between inner and outer walls are described by Tersoff-Brenner potential and Lennard-Jones potential respectively. Results show that new stable DWCNTs exist whose interlayer distances are not necessarily 0.34 nm. And these new DWCNTs show different mechanical behaviors as compared with the normal DWCNT.