Thallium selenides

According to Murakami, thallium forms thallous selenide, Tl₂Se, melting at 368°; thallothallic selenide, Tl₂Se.Tl₂Se₃, melting at 310°; and thallium sesquiselenide, Tl₂Se₃, decomposing at 265°. The equilibrium diagram is complex, there being two gaps of miscibility in the liquid state. The selenides are brittle solids. Thallous selenide may be precipitated by passing hydrogen selenide into aqueous thallous carbonate. It is decomposed by acids.