Identification of the electronic structure differences between polar isostructural FeO and CoO films by core-level soft x-ray spectroscopy

Abstract

The electronic properties of the FeO and CoO single layer thin films on Pt(111) were examined by core level soft X-ray spectroscopy. These oxygen terminated films are bilayer-thick and isostructural, Pt, Fe-Co, and O atoms stacked with small lateral shifts due to incommensurate relation with Pt(111). Probing occupied and unoccupied states projected on the oxygen atoms revealed states at the Fermi level suggesting orbital mixing with the metal substrate and also indicated an anisotropy in transition metal-oxygen bonding geometry. The differences in the core level spectral features were attributed to the substrate induced modification of the charge transfer energy and with an additional valence electron on Co.

Determination of the surface electronic structure of Fe3O4(1 1 1) by soft X-ray spectroscopy

“…Bulk electronic and magnetic structures of Fe 3 O 4 and Fe 2 O 3 have been investigated by XPS and XAS (and also by electron energy loss spectroscopy), many studies on the interpretation of O K-edge and Fe L-edge XAS spectra have been reported [15,[17][18][19][20][21]. Although there are few surface sensitive XPS measurements [22], so far no systematic XAS investigations on the local coordination and electronic structures of the surface atoms terminating iron oxide single crystal surfaces have been performed.…”