Sn-K and Pb-L3 EXAFS, X-Ray Diffraction, and 119Sn Mössbauer Spectroscopic Studies of Ordered β-PbSnF4 and Disordered Pb1-xSnxF2 (x = 0.3, 0.4) Solid Solutions and PbSn4F10: High Performance Fluoride Ion Conductors

Fully and partly disordered superionic conductors in the PbF2/SnF2 system have been studied using X-ray powder diffraction, 119Sn Mössbauer spectroscopy, and Pb-L3 and Sn-K EXAFS (extended X-ray absorption fine structure). X-ray diffraction is seriously limited because of the large degree of disorder at the metal site. The solid solution Pb1-xSnxF2 (x = 0-0.30) is fully disordered as is the stoichiometric compound PbSn4F10 (x = 0.80). On the …