Fluorine K-edge X-ray Absorption Spectroscopy of Lead(II) Tetrafluorostannate(II)

Abstract

Lead(II) tetrafluorostannate(II) (PbSnF₄) exhibits the highest conductivity among the reported fluoride ion conductors. The previous studies analyzed the diffusion mechanism of fluoride ion based on the crystal structure with the diffraction studies and the nuclear magnetic resonance measurements. In this study, the electronic structure of PbSnF₄ is investigated using fluorine K-edge X-ray absorption spectroscopy. The composition of Pb causes the electronic structure change of the vacant F-2p orbital which is the hybridized Pb-6s and Sn-5s orbitals. The electronic structure change is related to the tendency of the fluoride ion conductivity in Pb_1-xSn_xF₄.