Geometrical and Electronic Properties of the Clusters of C20 Cage Doped with Alkali Metal Atoms

Abstract

Using first-principles density-functional theory based on the generalized gradient approximation, we have investigated the geometrical and electronic properties of the pure C20 cage with D 3d symmetry and M@C20(M = Li, Na, K, Rb, Cs) clusters with I h symmetry. It is found that the interstitial M@C20 clusters are energetically stable and have strong total magnetic moments. The stability is analyzed through charge distributions on the atoms and the magnetism is explained through the degeneracy and fractional occupation of the molecular orbitals.