Thermochemische Untersuchungen zu den Systemen SE2O3-SeO2. V. Ytterbiumselenoxide auf dem Schnitt Yb2O3-SeO2/Thermochemical Investigations of Systems RE2O3-SeO2. V. Ytterbium Selenium Oxides on the Line Yb2O3-SeO2

The pure ternary phases on the line Yb₂O₃-SeO₂ in thermodynamical equilibrium have been synthesized by solid state reaction and characterized using X-ray powder diffraction and IR-spectroscopy. There exist three phases: Yb₂SeO₅, Yb₂Se₃O₉ and Yb₂Se₄O₁₁, the last one with a homogeneiety range extending a higher SeO₂-content. The thermal decompositions have been determined by total pressure measurements, and the thermodynamical data of the compounds have been derived. The phase diagram and the phase barogram have been established using the results of thermal analysis and total pressure measurements.