Stone–Wales transformation: Precursor of fracture in carbon nanotubes

The fracture strain of carbon nanotubes (CNTs) obtained by molecular dynamics is about 30%, which is much higher than the experimental results (10–13%). The present study shows that this difference results mainly from defects in CNTs. As the tensile strain reaches a few percent, defects are nucleated in the form of Stone–Wales transformation (90° rotation of a bond). A bond in the vicinity of rotated bond breaks as the tensile strain reaches about 13%, which agrees well with the experimental results. Therefore, the Stone–Wales transformation is the precursor of CNT fracture.