Ionic conductivity of -AgI

We have measured the silver-ion conductivity in single-crystal -AgI between 330 K and the -to- transition at 420 K by the complex impedance method. The conductivity is approximately isotropic, with pronounced curvature in the log10(T) versus 1T representation. We found the surface conduction perpendicular to c to be significant. Detailed measurements in the vicinity of the -to- transition show no evidence for unusual pretransition silver sublattice melting.