DC conductivity and dielectric properties in silver chloride, revisited

The anomolous DC ionic conductivity of silver chloride at high temperatures is analyzed quantitatively with the aid of mean field models and classical Monte Carlo simulations. It is found that the conductivity anomaly in silver chloride along with the exponential increase of the dielectric constant at high temperatures may be explained by referring to the idea of a "soft lattice", wherein silver ions are increasingly free to move about their regular lattice sites as the temperature rises. This wide ranging of silver ions leads to the formation of transient dipoles, which have the dual effect of increasing the dielectric constant and decreasing the free energy of the lattice.