Core-level spectroscopic study of FeO and FeS2

Abstract

The electronic structures of iron oxide and iron disulfide (FeO and FeS2) have been examined using x-ray emission spectroscopy and other core-level spectroscopies. We compare the excitation spectra for charge neutral excitation (x-ray emission) and ionization (photoelectron spectroscopy) at the 2p edge and with final-state 3s holes. At the Fe L-2-edge, the branching ratio of L,6 to La emission is much higher for high-spin FeO than for low spin FeS2, similar to previous observations of Heusler alloys. We suggest that there is a general trend toward high branching ratios for magnetic 3d materials and low branching ratios for nonmagnetic materials. Resonant inelastic x-ray spectra of FeO with 3s final-state holes show a smaller exchange splitting than the corresponding x-ray photoemission spectroscopy spectra with 3s hole states.