Abstract: | The Tl2Se-As2Se3-Se system in the equilibrium crystalline state was studied by differential thermal analysis, X-ray powder diffraction, and
measurements of emf relative to a thallium electrode within the temperature range 300–400 K. An isothermal section of the
phase diagram at 300 K was constructed. The formation of ternary compounds Tl3AsSe4, TlAsSe2, and Tl3AsSe3 was confirmed, and the locations of their phase regions were determined. From the emf measurement data, the partial molar
functions of thallium in alloys, the standard thermodynamic functions of formation, and the standard entropies of the above
ternary compounds were calculated. |