6533b851fe1ef96bd12a979f

RESEARCH PRODUCT

Stoichiometry-related Auger lineshapes in titanium oxides: Influence of valence-band profile and of Coster-Kronig processes

Roberto GotterA. MorganteD. ChandesrisHélène MagnanJacques JupilleAlberto VerdiniP. Le FèvreM.a. ArrioSylvie BourgeoisJ. DangerJ. DangerJ. Danger

subject

PACS: 71.20.-b 32.80.Hd 77.84.Bw 82.80.Pvoxidationchemistry.chemical_element02 engineering and technologyceramics01 natural sciencesElectron spectroscopy71.20.-b; 32.80.Hd; 77.84.Bw; 82.80.PvIonAugerX-RAY-ABSORPTION; SURFACE-DEFECTS; RUTILE TIO2; Resonant AugerMetalsymbols.namesakephotoelectron spectra0103 physical sciencesRUTILE TIO2titanium010306 general physicstitanium compoundsAuger electron spectroscopyFermi levelvalence bandsResonant Auger021001 nanoscience & nanotechnologyCondensed Matter PhysicsSURFACE-DEFECTSElectronic Optical and Magnetic Materialsstoichiometrychemistryvisual_artX-RAY-ABSORPTIONsymbolsvisual_art.visual_art_mediumFermi levelspectral line breadthAuger electron spectraAtomic physics0210 nano-technologyStoichiometryTitanium

description

International audience; The ability to determine the nature and the occurrence of defects is a central need of ceramic surface chemistry. In titanium oxides, the Ti-LMV 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 Ti-L2,3 edges in TiO2, TiO2–x and metallic titanium provide a clear evidence that the evolutions of the Ti-LMV Auger line shape are due to drastic changes in the valence-band profile and in the probability of L2L3V Coster-Kronig decay processes when a fraction of titanium ions is reduced. Both are shown to be consequences of the filling of Ti-3d states near the Fermi level on defects sites. These conclusions are confirmed by Auger-photoelectron coincidence experiments.

yearjournalcountryeditionlanguage
2004-04-19
10.1103/physrevb.69.155421https://hal.archives-ouvertes.fr/hal-00004486