By using empirical-potential and tight-binding models, a study was made of the structure and stability of atomic-scale irradiation-induced defects on the walls of C nanotubes. Because atomic vacancies were the most prolific but metastable defects which appeared under low-dose low-temperature ion irradiation, the temporal evolution of single vacancies and vacancy-related defects (which isolated vacancies could become) was modelled and their lifetimes at various temperatures were calculated. Scanning tunnelling microscopic images of irradiated nanotubes with defects were also simulated by using the tight-binding Green’s function technique. The simulations demonstrated that the defects survived long enough at low temperatures to be detected by scanning tunnelling microscopy and that different defects manifested themselves in scanning tunnelling microscopy images in various ways, all of which made it possible to detect and distinguish the defects.

Stability of Irradiation-Induced Point Defects on Walls of Carbon Nanotubes. A.V.Krasheninnikov, K.Nordlund: Journal of Vacuum Science & Technology B, 2002, 20[2], 728-33