First-principle study of Au n Sc m (n=1-7, m=1,2) clusters

The geometries, stabilities, electronic, and magnetic properties of AunScm (n= 1-7, m=1,2) clusters have been systematically investigated by density functional theory. It is shown that the most stable structures of AunSc (n=1-7) clusters favor planar structure and Sc atom is prone to occupy the center site of Au atoms ring. For AunSc2 clusters, the 3d configurations become the lowest energy structure for n≥3; the growth is based on triangle bipyramid structure of Au3Sc2 cluster except Au4Sc2. The second-order energy difference and the fragmentation energy show Au3Sc, Au5Sc, Au3Sc2 and Au6Sc2 clusters possess relatively higher stabilities than their neighbor size. The doping of Sc atom can greatly improve the stability of Au clusters. The doped one Sc atom changes the odd-even alternation trend of gaps in Au n . The two doped-Sc atoms enhance chemical activity of Au n in most cases. The total magnetic moments with even valence electrons are quenched on the whole due to electron pairing effects. The averaged coordination number for Sc should be major reason for reduce of local magnetic moments of Sc atom with cluster size increasing in cluster with odd valance electrons. The total magnetic moments in AuSc and Au2Sc2 are no quenched due to the smaller coordination number, the charge transfer and weak hybridization between the Sc and Au atoms.