Identification of charge-transfer satellites in the photoelectron spectra of SrTiO3 by high energy resonant photoelectron spectroscopy
Joseph C. Woicik, C. Weiland, Abdul K. Rumaiz
We have studied the satellite structure appearing in the Ti 1s and Ti 2p core-photoelectron spectra of the transition-metal oxide SrTiO3 by high energy resonant photoelectron spectroscopy (HERPES). We demonstrate experimentally that the two satellites observed in both spectra are due to ligand to metal shake-up charge transfer. This assignment is based on the energies of the different resonant K-L2L3 Auger decays that follow Ti 1s photo-excitation. The satellites are attributed to ligand 2p t2g → metal 3d t2g and ligand 2p eg → metal 3d eg monopole transitions that are consistent with energy assignments and intensities based on molecular orbital theory. Our data are also shown to be consistent with recent theoretical calculations.