The effects of germanium on the configurations and magnetic moments of nickel clusters

We report ab initio calculations of the structures, binding energy and total spin moment of NinGe (n = 2–12) clusters using all electron density-functional method. Our results show that the doped Ge makes the stability of NinGe clusters weakened as compared with pure Nin+1 clusters. The Ni6Ge and Ni9Ge clusters possess relatively higher stability. Compared with the magnetism of pure Nin+1 clusters, the magnetism of NinGe (n = 2–10) clusters is reduced, which is attributed mainly to the nor-magnetism Ge element and the weakening of spin polarization of the Ni atoms. For Ni11Ge and Ni12Ge, the spin polarization of Ni atoms is enhanced. Furthermore, it can be interpreted that the size effect which should contribute to the increase of the magnetic moment for Ni12Ge, and the surface enhance effect should be responsible for the increase of the magnetic moment of Ni11Ge.