Structural, Electronic, and Magnetic Properties of Mixed V13?xRhx (x = 0 to 13) Clusters

Using an empirical many-body potential, we performed Genetic Algorithm (GA) to determine the ground-state atomic configurations of V13—xRhx (x = 0 to 13) clusters. The lowest-energy structures of both bimetallic and pure (x = 0 and 13) clusters are deformed icosahedra. In general, there is a tendency for Rh atoms to be segregated at the surfaces of the bimetallic clusters, although this effect can coexist with ordering. Based upon the optimized geometries, the ground state electronic and magnetic properties of these clusters are calculated by using an spd-band model Hamiltonian in the unrestricted Hartree-Fock approximation. Due to the strong coupling of the electronic states of Rh and V atoms, the electronic structure and the magnetism of these clusters vary completely with the change in the ratio of the two classes of atoms. The average magnetic moments per atom for Rh and V atoms , , as well as the average magnetic moment for these clusters oscillate as functions of the numbers x of Rh atoms.