Hot stage X-ray diffractometer studies on Ag2PbI4 and Ag4PbI6

Mixtures of AgI and PbI₂ cooled from the melt result in the peritectic formation of a fast ion conducting phase centred about Ag₄PbI₆, which is face centred cubic with a = 6.33(5)A; this phase exhibits high electrical conductivity. On cooling to about 125°C, dissociation occurs to γAgI and PbI₂, accompanied by the transient formation of another phase, centred about Ag₂PbI₄. A modified form of the T-x section of the equilibrium phase diagram at AgI concentrations greater than 60 mole % and below 300°C is proposed.