Geometries, stabilities, and magnetic properties of MnGen (n = 2-16) clusters: Density-functional theory investigations

Mn-doped germanium clusters have been systematically investigated by using the density-functional approach. It was found that doping of one Mn atom contributes to strengthening the stability of the germanium framework. Maximum peaks of the second-order energy differences were observed for clusters of sizes n = 5, 9, 12, and 14, implying their relative higher stability than other-sized MnGen clusters. The highest occupied molecular orbital and lowest unoccupied molecular orbital (HOMO-LUMO) gaps of the MnGen clusters, with the exception of MnGe14, are generally lower than the corresponding pure germanium clusters. We also found that charge always transfers from manganese to germanium atoms in all sized MnGen clusters and the magnetic moment of the Mn atom does not quench when embedded in all sized Gen (n = 2-16) clusters.