hexachloroplatinates

Hexachloroplatinates are salts containing the hexachloroplatinate anion, [PtCl6]^2-. This anion consists of a central platinum atom in the +4 oxidation state coordinated to six chloride ligands. The hexachloroplatinate ion is generally stable and soluble in water.

Common hexachloroplatinates include potassium hexachloroplatinate (K2[PtCl6]) and ammonium hexachloroplatinate ((NH4)2[PtCl6]). These compounds are typically yellow crystalline solids. They are often formed by the reaction of platinum metal or platinum salts with chloroplatinic acid (H2[PtCl6]) in the presence of a chloride source.

Historically, hexachloroplatinates have been important in platinum chemistry. Potassium hexachloroplatinate, for instance, was used as a precursor for the preparation of other platinum compounds and for electroplating of platinum. Ammonium hexachloroplatinate has been used in photography and as a precursor for platinum catalysts.

These compounds can be hazardous. They are generally considered irritants, and some are known sensitizers, capable of causing allergic reactions upon repeated exposure. Handling should be done with appropriate safety precautions. Decomposition of hexachloroplatinates, particularly upon heating, can release toxic fumes.