Cadmium Thiophosphates

Cadmium Thio-orthophosphate, Cd₃(PS₄)₂, is obtained as a white crystalline powder by heating phosphorus pentasulphide with cadmium chloride or sulphate. It behaves similarly to the corresponding zinc salt.

Cadmium Thio-hypo phosphate, Cd₂P₂S₆, is prepared, similarly to the corresponding zinc salt, in orange-yellow biaxial crystals. It decomposes partially in moist air. Aqueous alkalies liberate some hydrogen sulphide from it, and nitric acid acts on it very rapidly.

Cadmium Thio-pyrophosphate, Cd₂P₂S₇, was obtained similarly. The white crystalline powder decomposes rapidly in air but is resistant to acids, and even hot concentrated nitric acid has only a slight action.