First-principle study of AunFe (n = 1-7) clusters

The geometrical structures, relative stabilities, and magnetic moments of iron-doped gold clusters, AunFe (n = 1-7), have been investigated using density functional method B3LYP and LanL2DZ basis set. Many low-lying isomers of the AunFe clusters are obtained along with their electronic states. The results show that the ground-state AunFe isomers possess a linear structure for n = 1-2 and a planar structure for n = 3-7. The relative stabilities of AunFe clusters for the ground-state structures are analyzed based on the averaged binding energies, fragmentation energies, second-order difference of energies, and HOMO-LUMO energy gaps. It is found that the Au2Fe and Au4Fe clusters are magic clusters with high chemical stability. The magnetic moment calculations for the ground-state AunFe clusters, which are magnetic, indicate that the total magnetic moment of the clusters is mainly localized on the Fe atom and two magic clusters are larger in total magnetic moments than others.