An earlier structural model for binary silicate melts and glasses is extended to zinc chloride-alkali metal chloride systems. The evaluation of the available thermodynamic and phase diagrams data for the MCl-ZnCl2 (M = Li, Na, K) binary systems have been carried out using the structural model for the liquid phase. This thermodynamic model is based on the assumption that each alkali chloride produces the depolymerization of ZnCl2 network with a characteristic free-energy change. A least-squares optimization program permits all available thermodynamic and phase diagram data to be optimized simultaneously. In this manner, data for these binary systems have been analysed and represented with a small number of parameters. (C) 2010 Elsevier B.V. All rights reserved.