It was recalled that the Stone–Wales defect was a dipole 5–7 ring pair in an hexagonal network and was one of the most important defective structures in C nanotubes that could affect their mechanical, chemical and electronic properties. By using the extended Hückel method, the formation energy of Stone–Wales defects in C nanotubes was calculated. The formation energy of the defects was then fitted into a simple formula as a function of the tube radius and the orientation of the Stone–Wales defect in the tube. This result provided a convenient tool for studying thermodynamics and kinetics of Stone–Wales defects, as well as their interaction with other types of defects in C nanotubes.

Formation Energy of Stone–Wales Defects in Carbon Nanotubes. L.G.Zhou, S.Q.Shi: Applied Physics Letters, 2003, 83[6], 1222-4