New anionic conductor KSbF4 with fluorite structure

Abstract

A new fluoride ion conductor, β-form of KSbF4, was synthesized and characterized by the conductivity, DTA, XRD, and 19F NMR measurements. The low temperature modification, α-form, showed an irreversible phase transition at 455 K accompanied by a steep increase in conductivity. This high temperature modification was stable on cooling and belongs to a cubic system above 420 K with a disordered fluorite structure. 19F NMR linewidth measurement for this modification suggested a high conductivity due to the fluoride ion.