PHASE EQUILIBRIA ALONG THE Cu2GeSe3–Ag2GeSe3 ISOPLETH SECTION OF THE Cu2Se–Ag2Se–GeSe2 SYSTEM

DTA and XRD methods were used to study phase equilibria along the Cu2GeSe3–Ag2GeSe3 isopleth section of the Cu2Se–Ag2Se–GeSe2 system and its phase diagram was constructed. It was established that this section is non-quasibinary. In the composition range 0–55 mol% Cu2GeSe3, solid solutions on the basis of high-temperature modification of Ag8GeSe6 primarily crystallize from the melt, and in the range 55–100 mol% Cu2GeSe3 solid solutions based on Cu2GeSe3. Based of Cu2GeSe3, solid sub¬stitution solutions were identified, the length of which at 900 K is 20 mol%, and at room temperature – 10 mol%