Possible Ring Structures of Armchair Single-Walled Carbon Nanotubes

Abstract

Energetics and the electronic structure of various types of single-walled carbon nanotubes have been investigated by using Density Functional Theory. Armchair [n,n], zigzag [n,0] and chiral [n,m] C40H20 nanotubes have been considered. Calculations show that the armchair isomer is the most stable among the three types and they further reveal the factors that stabilize this isomer. Nucleus-independent chemical shift calculations indicate the aromaticity of the individual hexagonal rings in the carbon nanotubes and explain the extent of electron delocalization in them.