Density functional study of onion-skin-like [As@Ni12As20]3− and [Sb@Pd12Sb20]3− cluster ions

A comprehensive study of the structural and electronic properties of the interesting onion-skin-like [As@Ni12As20]3− cluster ion, characterized by Moses et al. [Science 300 (2003) 778], was carried out using a plane-wave based density functional theory. The calculated interatomic distances agree well with experiment. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) for [As@Ni12As20]3− are fivefold-degenerate with hu and hg symmetries, respectively, and its HOMO–LUMO gap is determined to be 0.2 eV lower than that of C60. The static dipole polarizability of [As@Ni12As20]3− is two times larger than that of C60. The optical gap of [As@Ni12As20]3− is redshifted by 1.4 eV relative to that of C60. The possibility of synthesis of [Sb@Pd12Sb20]3− is proposed.