Fullerenes with symmetrically arranged defects: Geometry and electronic structure

Recently, fullerene structures with symmetrically arranged pairs of pentagonal-heptagonal defects were proposed to explain the round shape of giant multilayer fullerene cages. Even though those proposed cages are defective, they belong to the icosahedral point group. Using the Tersoff-Brenner potential, we calculated the shape of the defective fullerenes. It is found that these fullerenes have a rounder shape than structures without defects. The electronic structure of the fullerenes with defects is also calculated within the Hückel approach. The electronic structures are closed and the energy gaps between bonding and antibonding orbitals are higher than those for fullerenes with no defects in almost all cases considered.