Structure, stability, and magnetism of Sc_nAl (n = 1-8,12) clusters:Density-functional theory investigations

摘要

Equilibrium geometries and electronic and magnetic properties of small Sc_nAl (n=1-8,12) clusters have been studied based on the density-functional theory with all-electron spin-polarized generalized gradient approximation.The calculated results show that the Al atom remains on the surface for n=1-8, but at the center of the Sc_(12)A1 cluster with a variable icosahedral structure (C_(3ν). Doping of the Al atom enhances stability of the scandium clusters. Maximum peaks are observed for clusters of n=3,6 on the size dependence of the second-order energy differences and fragmentation energies, implying that the two clusters possess relatively higher stability. This study also reveals that the Al atom is seen to induce significant changes in the magnetic property of the host cluster. Especially, the magnetic moment of the Sc_nAl cluster is quenched for5n,= a3nd,7, and the total magnetic moment of the Sc_(12) (fA7bo1 curlu tsSt μe1rc is9_ oμn(l1yBB3).