Atomic structure, electronic properties, and thermal stability of diamond-like nanowires and nanotubes

Density functional fight-binding calculations are used to investigate the structure, electronic properties, energy stability, and thermal behavior (0-1500 K) of extended monolithic (nanowires) and hollow (nanotubes) diamond-like carbon nanostructures. The results indicate that diamond-like nanowires and nanotubes may be both metallic and semiconducting, depending on their morphology and size. A new type of hybrid (sp(3) + sp(2)) nanostructure is identified, which has the form of a monlithic diamond-like (sp(3)) wire inside a graphite-like (sp(2)) shell. Diamond-like nanowires are shown to be more stable than nanotubes of comparable size.