A 2-layered ONIOM method was used to study the reaction of nitric oxides with a 5-1DB defect on the side-wall of a single-walled C nanotube. A suitable ONIOM model was chosen for calculation of the single-walled C nanotube, based upon analyses of the frontier molecular orbitals, local density of states, and natural bond orbitals. The calculations clearly indicated that the 5-1DB defect was the chemically active center of the single-walled C nanotube. In the reaction of nitric oxides with the defected single-walled C nanotube, the 5-1DB defect site could capture a N atom from nitric oxides, yielding the N-substitutionally doped single-walled C nanotube. The reaction pathway was explored in detail. The results confirmed the chemical reactivity of the 5-1DB defects of the single-walled C nanotubes, indicated that the 5-1DB defect was a possible site for the functionalization of the single-walled C nanotubes and demonstrated a possible means for fabricating position controllable substitutionally doped single-walled C nanotubes with a low dopant concentration under mild conditions, via simple chemical reactions.

Chemical Reaction of Nitric Oxides with the 5-1DB Defect of the Single-Walled Carbon Nanotube. L.V.Liu, W.Q.Tian, Y.A.Wang: Journal of Physical Chemistry B, 2006, 110[5], 1999-2005.