Electronic, vibrational dispersions and alkali-halides encapsulation in carbon nanotubes

Density functional calculations of electronic and vibrational dispersion energies for prestine graphite and single-walled carbon nanotubes (SWCNT) are presented. Optimized parameters for nonlocal norm-perserving pseudopotentials which replace the potential field due to core electrons are given and the valence electrons are treated with linear combination of localized atomic orbitals. The effect of encapsulation of carbon nanotubes with alkali-halide matrices is numerically investigated. The electronic band structure of encapsulated SWCNT is noticeably modified and hence its optical properties.