Translational dynamic friction analysis of double-walled carbon nanotubes.

Conflicting results on the effects of commensurability, overlap area, helicity and end configuration of double-walled carbon nanotubes (DWCNTs) on translational intertube friction have been reported. We perform molecular dynamics simulations on DWCNTs with different commensurabilities, overlap areas, helicities and end configurations to analyse the intertube friction behaviour and clarify these results. It is found that commensurability and overlap area play an insignificant role, while the atomic configurations of nanotube ends play a dominant role: armchair, normal and reconstructed zigzag ends contribute little to intertube friction; while the irregular ends with dangling atoms greatly increase the friction force. This end effect may also explain the role of helicity in the intertube friction. Implications of the end effect on experimental observations are also discussed. [ABSTRACT FROM AUTHOR]