0000000000858260

AUTHOR

Roberto Gotter

showing 3 related works from this author

Intra-atomic versus interatomic process in resonant Auger spectra at the TiL23edges in rutile

2001

The two components of the Ti ${L}_{23}{M}_{23}V$ Auger transition recorded on a stoichiometric rutile crystal are identified as ${L}_{2}{M}_{23}V$ and ${L}_{3}{M}_{23}V$ contributions. This assignment is evidenced by concordant data relative to resonances of the LMV decay at the Ti ${L}_{23}$ thresholds and to Auger emission recorded in coincidence with the ${2}_{1/2}$ and ${2}_{3/2}$ photoemission at a photon energy far above the Ti ${L}_{23}$ edges. The ${L}_{3}{M}_{23}V$ transition is shown to follow either the direct photoexcitation of a ${2}_{3/2}$ electron or the fast Coster-Kronig decay of a ${2}_{1/2}$ photohole. Although specific LMV contributions related to valence orbitals are id…

CrystalPhysicsValence (chemistry)Atomic orbitalElectronPhoton energyAtomic physicsElectron spectroscopySpectral lineAugerPhysical Review B
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Stoichiometry-related Auger lineshapes in titanium oxides: Influence of valence-band profile and of Coster-Kronig processes

2004

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.…

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
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Multiple scattering approach for two-electron resonant emission studied by angle-resolved coincidence spectroscopy.

2008

International audience; We have developed a generalization of the multiple-scattering formalism to deal with Auger-photoelectron coincidence spectroscopy APECS in the solid state. We have merged the exact atomic treatment of the angular correlations between the two electrons and the single-particle approach, on which the multiplescattering description of condensed matter relies. This allows the recovering, even in extended systems, of the entangled form of the electron-pair wave function characterizing the coincidence angular diffraction pattern. In the atomic limit our formalism correctly reproduces the cross section, as calculated within the statistical-tensors approach, usually employed …

ABSORPTION FINE-STRUCTUREPhysicsDiffraction[PHYS]Physics [physics]ScatteringSolid-state02 engineering and technologyElectron021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciencesCoincidenceElectronic Optical and Magnetic Materials0103 physical sciencesPHOTOELECTRONELECTRONAtomic physics010306 general physics0210 nano-technologySpectroscopyAnisotropyWave functionPACS 79.60.Bm
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