Decay Channels For The Ti(2p(1/2)) Core Hole Excitations In Tio2 Observed By X-Ray Raman Scattering

We present high-resolution x-ray fluorescence spectra, corrected for self-absorption, following resonant excitation of a Ti(2p(1/2)) electron in TiO2. Several transitions are studied that show complex behavior as a function of photon excitation energy, indicative of interaction in the excitation and decay channels. Three peaks are identified as transitions resulting from the excitation of a 2p(1/2) electron, one of them corresponding to direct valence emission with a 3d spectator electron and the other two to participator emission following the Coster-Kronig decay of the 2p(1/2) hole. Additional emission features at higher photon energies correspond to valence emission in the presence of a charge-transfer excitation that has been found in the 2p x-ray photoelectron spectroscopy spectrum, and also in the x-ray absorption spectrum. A detailed analysis of the energy dispersion versus excitation energy provides information about the dynamical processes involved. The results are interpreted in terms of the calculated band structure of the compound.