Study on the structures, stabilities, electronic configurations of anion gold clusters and anion Cr-doped gold clusters

Abstract:

The ground state structures, stabilities, electronic configurations and magnetic properties of anion gold clusters and anion Cr-doped gold clusters have been systematically investigated by density functional theory. Our results show that 〖"Au" 〗_"n+1" ^"-1" (n=1~10) clusters and AunCr-1 (n=1~6) clusters are planar configurations and AunCr-1 (n=7~10) clusters are body structures. Remarkably, the stabilities of anion gold clusters can be improved by Cr-doping. The dissociation energies and second-order difference energies results indicate that the even number of 〖"Au" 〗_"n+1" ^"-1" clusters and AunCr-1 clusters are more stable than adjacent odd clusters. The charges of the orbitals indicate that the incorporation of Cr atom makes the spd hybridization of Au atoms more complicated, and the Cr atoms are the main acceptors of the valence charge in AunCr-1 clusters. The results of orbital magnetic moment show that the electronic structure of 〖"Au" 〗_"n+1" ^"-1" clusters exhibit obvious open-closed shell structures with size increasing and the electronic structures of AunCr-1 clusters are Open shell. In this regime, the magnetic moment of 〖"Au" 〗_"n+1" ^"-1" clusters is mainly contributed by the Au5d orbitals, while the magnetic moment of AunCr-1 clusters is mainly contributed by Cr3d orbitals.

Key words:Density functional theory; Gold cluster; Stability; Magnetic moment