Electronic structure of Mn2O−: ferromagnetic spin coupling stabilized by oxidation

The electronic structure of Mn2O− was investigated by photoelectron spectroscopy and the density-functional theory (DFT). The cluster anion was found to possess a spin magnetic moment as large as 11 μB (Bohr magneton) due to ferromagnetic coupling between the spins localized on each manganese site. The ferromagnetic state gains substantial stability via superexchange-type interaction through an oxygen atom at the bridge site. This mechanism is manifested in its electronic structure, which exhibits significant hybridization among the Mn 3d, Mn 4s, and O 2p orbitals.