First-Principles Simulations of Chiral Double-Wall Carbon Nanotubes

we discuss the use of helical symmetry to carry out first-principles band structure calculations of double-wall carbon nanotubes (DWNTs). While several first-principles calculations have been carried out for double-wall armchair nanotubes using translational symmetry since the early work by Charlier and Michenaud in 1993, few calculations have been carried out for double-wall carbon nanotubes containing chiral single-wall nanotubes. The use of helical symmetry reduces the size of the unit cell, and consequently reduces the computational difficulty of calculating the electronic structure of chiral DWNTs. Calculations carried out for a range of interlayer separations show a minimum cohesive energy around 0.35 nm as expected from experimental results. (C) 2008 Wiley Periodicals, Inc. Int J Quantum Chem 108: 2943-2949, 2008