Electronic structure of the ε phase in an Fe-40% Mn alloy

The e phase in the FeMn alloy was stabilized by a shear deformation under pressure. X-ray photoelectron spectra (XPS) of this phase were obtained for the first time and interpreted based on the band-structure calculations for a model ordered alloy with the NiAs structure. The observed high intensity of XPS spectra near the Fermi level is related to the dominant contribution of Mn d states. The distribution of electronic charge density was calculated; the results suggest that bonds between Fe and Mn atoms, as well as between Fe atoms, have a significant covalent contribution.