Resonant inelastic soft-x-ray scattering from valence-band excitations in 3d0 compounds

Ti and Mn ${\mathrm{L}}_{\mathrm{\ensuremath{\alpha}},\mathrm{\ensuremath{\mathrm{B}}}}$ x-ray fluorescence spectra of ${\mathrm{FeTiO}}_{3}$ and ${\mathrm{KMnO}}_{4}$ were measured with monochromatic photon excitation on selected energies across the ${\mathrm{L}}_{2,3}$ absorption edges. The resulting inelastic x-ray-scattering structures and their changes with varying excitation energies are interpreted within the framework of a localized, many-body approach based on the Anderson impurity model, where the radiative process is characterized by transitions to low-energy interionic-charge-transfer excited states. Sweeping the excitation energy through the metal 2p threshold enhances the fluorescence transitions to the antibonding states pushed out of the band of continuous states due to strong metal 3d--ligand 2p hybridization and matching the low-photon-energy satellites in the spectra. Based on the energy position of these charge-transfer satellites with respect to the recombination peak the effective metal 3d--ligand 2p hybridization strength in the ground state of the system can be estimated directly from the experiment.