“…The system Cu 2 Se-PbSe-As 2 Se 3 is bounded by three quasi-binary systems, Cu 2 Se-As 2 Se 3 , Cu 2 Se-PbSe and PbSe-As 2 Se 3 . The Cu 2 Se-As 2 Se 3 system is well-studied [1][2][3]; it features the formation of one ternary compound, CuAsSe 2 , by a peritectic reaction, L p1 +Cu 2 Se↔CuAsSe 2 . CuAsSe 2 crystallizes in space group R3 with the lattice parameters a = 1.4025 nm, c = 0.961 nm, structure type Cu 7 As 6 Se 13 [4].…”