A first-principles study was made of single-walled carbon nanotubes with a bamboo-shape and containing pentagon-pentagon fusion defects. Sharp resonances occurred on the bamboo-shaped nanotubes as a strong density of electronic states localized at carbon atoms adjacent to the partitions while, at the partition, the localized density of states was greatly depleted. A strong defect state at -0.1eV below the Fermi level was generated, and the band gap was narrowed for bamboo-shaped (10,0) nanotubes. Sharp resonant states were observed in the valence and conduction bands of bamboo-shaped (12,0) nanotubes. The resonant states were attributed to pentagon defects, as exemplified by a study of a (5,5) nanotube with a pentagon-pentagon fusion ring. A high chemical reactivity of the topological defects of the bamboo-shaped nanotubes was correlated with the presence of localized resonant states.

First-Principles Study of Carbon Nanotubes with Bamboo-Shape and Pentagon-Pentagon Fusion Defects. S.H.Lim, W.Ji, J.Lin: Journal of Nanoscience and Nanotechnology, 2008, 8[1], 309-13