The Computation of Elastic Constants of Double Wall Carbon Nanotubes Based on the Finite Element Method Considering Van Der Waals' Force

Abstract

Based on the finite element method (FEM), we study the elastic constants of double-wall carbon nanotubes (DWCNTs). In the models, the Lennard-Jones potential function is used to consider the Van der Waals' force between non-bond atoms from different layers. The variations of the elastic constants with the diameter and the aspect ratio of the internal layer nanotube are investigated systematically. The computational results indicate that for both the armchair and the zigzag DWCNTs, the elastic moduli are generally lower than those of the single-wall carbon nanotubes with the same chirality as the internal and external layers. With the increase of the diameter and the aspect ratio of the internal layer carbon nanotubes, the elastic constant of DWCNTs will fall to a stable value.