Physicochemical study of silicon and zirconium phosphates

Phase formation in MO2-P2O5 (M=Si, Zr) systems, as well as the properties and structures of formed phases were investigated. The study was conducted by the methods of thermal, X-ray, microscopic with successive chemical analyses and by the method of IR-spectroscopy. Formation of 4 types of compounds was established in the system: oxydiphosphate, monophoshate, diphosphate and polyphosphate. (ZrO)2P2O7 compound has two polymorphous forms with 1100 deg C transformation temperature. Zirconium diphosphatye is characterized by two forms with back transformation at 300 deg C. Oxydiphosphate is the most stable compound. Phase diagrams o f the systems of compounds (melting points, lattice parameters, refractive indeces, densities) are presented