ELECTRONIC PROPERTIES OF C58BN HETEROFULLERENES

Abstract

Recent studies of electronic structure of solid fullerenes have revealed many interesting properties of these systems. Here, we are interested in the effects of substitution of two carbon atoms by nitrogen and boron. We calculate the electronic structure of the C 58 BN cluster as well as its dispersion relation in the fcc crystalline phase. We consider the two cases where the nitrogen and the boron are neighbors and the case where they are situated far apart. In our all-electron calculation, we adopt the mixed basis approach in which we include the 1s and 2p orbitals in addition to plane waves. We investigate the existence of the donor and acceptor levels in both cases where N and B are neighbors and where they are apart. Furthermore, the electronic density in their neighborhood will be largely affected. The double bond which existed in the C 60 case is now replaced by a single bond. The consequences of substitutional doping, which is to create donor and acceptor levels and to broaden the valence and conduction bands; the anisotropy in the band dispersion; and the eventual relaxation of the nitrogen and boron atoms to a new position are also discussed.