SPIN-DEPENDENT LOCAL-DENSITY OF EMPTY ELECTRONIC STATES IN FENI3

The electronic structure of the magnetic compound FeNi3 is investigate d by spin-resolved soft-x-ray appearance potential spectroscopy. The s pectra which reflect the local densities of empty states on the Fe and Ni sites in this compound are compared with results for the pure elem ents. A detailed description and interpretation of the experimental sp ectra is achieved by a comparison with theoretical spectra. They were calculated, within a single-particle picture, from the underlying elec tronic structure including a proper treatment of transition matrix ele ments. The experimentally observed energetic shifts and spin-asymmetry changes between the pure elements and the compound are understood as a consequence of changes in the spin-dependent local densities of stat es and in the core-level binding energies. In particular, this allowed us to determine the changes in the binding energies for the 2p(3/2) s tates of Fe and Ni in the compound with respect to the pure elements.