Platinum(II) chloride exists in two crystalline forms (polymorphs), but the main properties are somewhat similar: dark brown, insoluble in water, diamagnetic, and odorless.

Aqueous solutions of H2PtCl6 can also be reduced with hydrazinium salts, but this method is more laborious than the thermal route of Kerr and Schweizer.

Although PtCl2 can form when platinum metal contacts hot chlorine gas, this process suffers from over-chlorination to give PtCl4.

These transformations entail depolymerization via cleavage of Pt-Cl-Pt linkages: Addition of ammonia gives initially "PtCl2(NH3)2", "Magnus's green salt", also described as [Pt(NH3)4][PtCl4].

Many complexes have been described, the following are illustrative:[7] Several of these compounds are of interest in homogeneous catalysis in the service of organic synthesis or as anti-cancer drugs.