Solid-phase reactions in the Y2O3-Mn2O3 system

Conditions of yttrium manganite synthesis of various structure in air and vacuum are considered, as well as kinetic patterns of synthesis reaction and influence of various methods of synthesis on the character of structural transformations in the system Y2O3-Mn2O3. Use was made of methods of chemical phase, X-ray diffraction analyses and infrared spectroscopy. The initial mixture of oxides of Y and Mn in the ratio 1:1 was calcined in air and vacuum in the temperature range 700-1400 deg C. The data of analyses indicated the formation of YMnO3 of hexagonal structure in the range of 800-1300 deg C. In the range of 850-1100 deg C YMn2O5 as a by-product was formed. The complete phase analysis of the mixture Y2O3+Mn2O3 (1:1) is given. It follows from comparison of kinetic curves that the conversion degree in the temperature range 850-1100 deg C is much higher in air than in vacuum