Multiscale modeling of carbon nanotubes under axial tension and compression

In this paper, we study the elastic and plastic properties of single-walled carbon nanotubes (SWCNTs) under axial compression and tension. The present work employs molecular dynamics (MD) as well as a multiscale technique where a handshaking region between MD and tight-binding (TB) is described and implemented. The interaction forces between the carbon atoms are calculated based on the second-generation reactive empirical bond-order potential, TB derived forces, as well as long-range Lennard-Jones potential. A smooth cutoff Lennard-Jones with switch function is also explored. The detection of sideway buckling due to the asymmetrical axial compression is reported and discussed. This sideway buckling phenomenon is observed when using both pure MD and MD/TB multiscale models. The viability of the presently developed handshaking region between MD and TB in CNTs under axial compression and tension is thus validated.