Pb LIII-edge EXAFS and XANES analyses on the structural environment of lead in PbO–Ga2O3 glasses

Pb LIII-edge absorption spectra of PbO–Ga2O3 glasses were analyzed and the local environment of lead in glasses was proposed. A single-shell fitting of Pb LIII-edge EXAFS (extended X-ray absorption fine structure) spectra of three PbO–Ga2O3 glasses showed that the Pb–O bond distances were between 0.229 and 0.231 nm with the oxygen coordination numbers between 3.3 and 3.5. Comparison of the absorption peaks in the pre-edge region of the Pb LIII-edge XANES (X-ray absorption near edge structure) spectra between glasses and other reference crystals indicated that the Pb2+ ions form either PbO3 or PbO4 polyhedra. These polyhedra are connected through either two- or three-coordinated oxygens similar to the configuration in PbSiO3 crystal.