ON RELATION BETWEEN ELECTRICAL CONDUCTIVITY AND PHASE TRANSITION OF NON-STOICHIOMETRIC CUPROUS SELENIDES

The electrical conductivity of non-stoichiometric cuprous selenide samples having various compositions was examined. Measurements were performed over the temperature interval where the phase transformation appears. Conductivity variations are explained considering non-stoichiometric cuprous selenide as the binary system (Cu2Se+ Se), in which alpha and beta phases in mutual equilibrium have different compositions, i.e. different concentrations of holes. The equations derived on the basis of an equilibrium process of phase transition describe the experimental curves with satisfactory agreement. Further consequences of such an approach to non-stoichiometric compounds are also discussed. © 1969.