Geometries, stabilities, and magnetic properties of (n=1–8) clusters: Density functional theory study

The geometries, stabilities, and magnetic properties of Cr@Aun (n=1–8) clusters have been studied by means of a density functional method PW91P86 and a LanL2DZ basis set. It is found that the Cr atom in the lowest energy Cr@Aun isomers tend to occupy the most highly coordinated position and the ground state configuration of the Cr@Aun clusters favor a planar structure, except for n=1. Maximum peaks are observed for the ground state Cr@Aun clusters at n=1, 5 on the size dependence of second-order energy differences, fragmentation energies, and HOMO–LUMO energy gaps, implying that the AuCr and Au5Cr clusters are magic clusters with relatively higher chemical stability. The magnetism calculations for the most stable Cr@Aun clusters, which have a charge transfer from chromium atom to gold atoms, demonstrate that the total magnetic moment of the clusters is mainly localized on the Cr atom