Temperature dependence of viscosity and density of the melts of quasibinary systems formed by copper chalcogenides

The temperature and concentration dependence of the kinematic viscosity and density of melts of quasi-binary systems formed of copper chalcogenides is investigated. The temperature dependence of the investigated properties is analyzed on the basis of the activated complex theory and of the fundamental equation of A. I. Bachinskii. It is shown that the postmelting effect is observed in all of the investigated melts, which is associated with the structural changes occurring on heating the melts. These changes consist in the transformation of a structurally inhomogeneous liquid into a homogeneous Newtonian liquid due to the thermal decay of clusters. It is also shown that the concentration dependence of viscosity exhibits a smooth behavior, and that of density exhibits a strictly additive behavior, which favors intermolecular interaction. The notions of this interaction follow from the treatment of the diagrams of state of appropriate quasi-binary systems and thermodynamic analysis.