Phase transitions and ionic transport in K3InF6
Abstract Four allotropic forms are shown for the K 3 InF 6 ternary fluoride by various experimental investigations, microcalorimetry, high temperature X-ray diffraction, optical and electrical measurements. The ac conductivity data of K 3 InF 6 are analysed in the Z *, M * and e * formalisms and the conductivity relaxation parameters are determined. Conductivity is of Arrhenius-type on either side of a transition temperature T tr ( T tr =488±10 K) which is very close to the Curie temperature T C ( T C =480±5 K). A conductivity jump of about one decade is observed at T C and that transition is of ionic-superionic type.