A study of the oxidation and fluorination of single-walled carbon nanotubes by the MNDO method

This paper reports on the results of MNDO calculations of the atomic adsorption of oxygen and fluorine on the surface of armchair and zigzag single-walled carbon nanotubes with a cylindrical symmetry. The calculations are carried out within the molecular cluster and ion-incorporated covalent-periodic cluster models at the modern quantum-mechanical semiempirical MNDO level. The electronic and energy characteristics of the oxidation and fluorination processes are analyzed, and the most energetically favorable oxide structure of the (6, 6) nanotube is determined. It is found that narrow-gap tubulenes show a tendency to metallic behavior as their surface is saturated with oxygen atoms. (C) 2002 MAIK "Nauka / Interperiodica".