The adsorption of C dimers on C nanotubes led to a rich spectrum of structures and electronic structure modifications. Barriers for the formation of C dimer induced defects were calculated and found to be considerably lower than those for the Stone-Wales defect. The electronic states introduced by the ad-dimers depend on defect structure and tube type and size. Multiple C ad-dimers provided a route to structural engineering of patterned tubes that may be of interest for nano-electronics.

Carbon Ad-Dimer Defects in Carbon Nanotubes. M.Sternberg, L.A.Curtiss, D.M.Gruen, G.Kedziora, D.A.Horner, P.C.Redfern, P.Zapol: Physical Review Letters, 2006, 96[7], 075506 (3pp)