The formation energy of Stone-Wales defects in carbon nanotubes was calculated using the extended Hückel method. The formation energies for the (10,10) armchair tube were found to be 5.4eV for a rotation angle of π/6 and 7.5eV for a rotation angle of π/2.

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