Unique Magnetic Moment and Electronic Properties for Fe(MgO)_n(n=1-8) Clusters: First-Principles Calculations

The geometries and electronic properties of Fe(MgO)_n are systematically investigated by the density functional theory. The results show that the doped Fe atom is prone to bond with the O atom, and Fe almost does not disturb the frame of (MgO)_n. The second-order energy difference, the fragmentation energies and the electron affinities show that Fe(MgO)₄ and Fe(MgO)₆ possess relatively higher stabilities. The HOMO-LUMO gaps of Fe(MgO)_n decrease obviously as compared with (MgO)_n. Almost equal unpaired electrons of the 3d state of the Fe atom in Fe(MgO)_n result in a nearly equal magnetic moment of Fe(MgO)_n.