Surface structure analysis of oxidized Fe(100) by low energy ion scattering

• Published in: Surface science 1987-03, Vol.182 (1), p.179-199
• Main Authors: Van Zoest, J.M., Fluit, J.M., Vink, T.J., Van Hassel, B.A.
• Format: Article
• Language: English
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/0039-6028(87)90095-1

The surface structures of differently prepared oxide layers on Fe(100) have been analysed using low energy ion scattering with time-of-flight analysis. The intensity of scattered 5 keV Ne + ions and neutrals was measured as a function of elevation and azimuth of the incoming beam at a constant scattering angle, producing photograms of clean as well as oxygen covered Fe(100) surfaces. The formation of the Fe(100) p(1 × 1)-O surface structure at full monolayer coverage was confirmed by measuring azimuthal distributions of reflected Ne + ions and neutrals at specular reflection and a scattering angle of 45 °. The oxygen atoms are found to be located in the fourfold symmetrical hollows of the substrate surface. From the O − recoil intensity as a function of the elevation angle of incidence at specular reflection it was calculated that the oxygen atoms are located at a distance of 0.56 ± 0.05 Å above the first substrate layer of iron atoms. A disordered oxide layer grown on Fe(100) at room temperature reconstructs at elevated temperatures leaving a well-ordered monolayer of oxygen on top of the surface. The surface structure of this oxygen monolayer appears to be identical with respect to the surface properties found for a single monolayer of oxygen on Fe(100).