Elastic axial buckling of carbon nanotubes via a molecular mechanics model

Based on a molecular mechanics model, analytical solutions for the critical buckling strain of single-walled achiral carbon nanotubes under axial compression are obtained. The results show that zigzag tubes are more stable than armchair tubes with the same diameter. Comparison with the results given by continuum mechanics model shows that the continuum mechanics model underestimates the critical buckling strain for smaller tubes if a Young's modulus for larger tubes (or for graphene sheets) is adopted. The effect of intertube van der Waals interaction from the inner tube of multi-walled carbon nanotubes on the buckling of the outermost tube is also qualitatively discussed and it is found that the van der Waals interaction has little effect on the critical buckling strain for double-walled carbon nanotubes.