Electronic structure observation of BaTiO using resonant X-ray emission at Ba L and Ti K edges

Yoshii, Kenji  ; Yoneda, Yasuhiro   ; Jarrige, I.*; Fukuda, Tatsuo  ; Nishihata, Yasuo; Suzuki, Chikashi ; Ito, Yoshiaki*; Yoshikado, Shinzo*; Fukushima, Sei*

We have studied the electronic properties of the ferroelectric barium titanate BaTiO using resonant X-ray emission spectroscopy (RXES) and X-ray absorption spectroscopy in the partial fluorescence mode (PFY-XAS) at the Ba L and Ti K absorption edges. Contrary to a previous study, we found no fine structure in the pre-edge area of the PFY-XAS spectrum at the Ba L3 edge, and no temperature-induced spectral change was observed across the Curie temperature (130C). This result is not supportive of the possible presence of the displacement around Ba at the Curie temperature. RXES spectra were measured at the Ti K edge. The photon energy of the emission peak is found to be nearly constant throughout the absorption edge for all three compounds. We deduce the Ti 3d states to have a delocalized character, in contrast with the Ba 5d states, a property which is consistent with the proposed scenario of the formation of electric dipoles in BaTiO.