Core-level X-ray photoelectron spectra and X-ray photoelectron diffraction of RuO2(110) grown by molecular beam epitaxy on TiO2(110)

We have measured Ru 3d, 4s, 4p and O ls high-resolution core-level X-ray photoelectron spectra, along with Ru 3d and O ls scanned-angle X-ray photoelectron diffraction angular distributions, for RuO2(110). The surfaces were prepared by oxygen-plasma-assisted molecular beam epitaxial growth of RuO 2 on TiO2(110). XPS spectral interpretation and the nature of the XPD scans strongly suggest that the complex line shapes are due to final-state screening effects, rather than the presence of Ru in oxidation states other than + 4. © 1997 Elsevier Science B.V.