Phase diagram of the quasi-binary system TlInSe2–SnSe2

The TlInSe2–SnSe2 quasibinary system was investigated using differential thermal and X-ray phase analysis methods. The phase diagram is of eutectic type (V type of the Rozeboom classification). The solid solution range of the ternary compound in the TlInSe2–SnSe2 system extends to 28 mol.% SnSe2 at 670 K. The eutectic point coordinates are 63 mol.% SnSe2 and 788 K.

Research highlights▶ The phase diagram of the quasi-binary system TlInSe2–SnSe2 was investigated by X-ray powder diffraction and differential thermal analysis. ▶ The system is of the eutectic type, with the invariant point at 63 mol.% SnSe2 and 788 K. The solid solution range of the ternary component extends to 28 mol.% SnSe2. ▶ The crystal structure of the solid solution alloy of 25 mol.% TlInSe2 was investigated (space group I4/mcm, a = 0.8091 nm, c = 0.6744 nm). A comparison with CuInSe2–SnSe2 and AgInSe2–SnSe2 systems is discussed.