The phase diagram of the 2Cuub>2ub>S + GeSeub>2ub> ↔ 2Cuub>2ub>Se + GeSub>2ub> reciprocal system was plotted.
The Cuub>8ub>GeSub>6ub>–Cuub>8ub>GeSeub>6ub> system was investigated.
The thermodynamic properties of the continuous Cuub>8ub>GeSub>6−xub>Seub>xub> solid solutions were calculated.