Theoretical Investigation of Small Diameter Single-Wall Carbon Nanotubes

Abstract

Density functional theory calculations were carried out to obtain the geometries, electronic band structures and the radial breathing mode frequencies of 23 single wall carbon nanotubes (armchair, zigzag as well as chiral tubes) within the diameter range of 0.3–0.8 nm. These parameters differ from those obtained from simple graphene wrapping and depend not only on the diameter but the chiral angle as well. In particular, the frequencies of the radial breathing mode do not follow a simple 1/d behavior for small diameters, starting from ≈0.7 nm.