Dynamical behavior of x-ray absorption and scattering at the L edge of titanium compounds: Experiment and theory

Detailed experimental results and model caclulations for the evolution of t he x-ray fluorescence in the vicinity of the L absorption edge of titanium in metallic Ti and TiO and insulating TiO2 and BaTiO3 are presented. Behavi or characteristic of x-ray Raman scattering was found in all samples. We de velop a model that describes the valence band emission below the L-3 absorp tion threshold in terms of the calculated partial density of states and the Kramers-Heisenberg x-ray scattering formalism. Linear muffin-tin orbital b and structure calculations were used for the projected density of states in the model. In the region below the L-3 absorption edge very good agreement between experiment and the model was found for all compounds. We propose a mechanism for the energy shift of the emission spectra for TiO2 and BaTiO3 . An explanation of the Raman energy loss in terms of the excitation of a v alence electron into localized states of d symmetry in the conduction band is also provided. [S0163-1829(99)01004-8].