Abstract
The ability to determine the nature and the occurrence of defects is a central need of ceramic surface chemistry. In titanium oxides, the Auger decays line shape is very sensitive to the titanium degree of oxidation, and has long been empirically used as a qualitative probe of the stoichiometry. In the present work, resonant Auger and resonant valence-band measurements at the edges in and metallic titanium provide a clear evidence that the evolutions of the Auger line shape are due to drastic changes in the valence-band profile and in the probability of Coster-Kronig decay processes when a fraction of titanium ions is reduced. Both are shown to be consequences of the filling of states near the Fermi level on defects sites. These conclusions are confirmed by Auger-photoelectron coincidence experiments.
- Received 3 October 2003
DOI:https://doi.org/10.1103/PhysRevB.69.155421
©2004 American Physical Society