Potassium Thiocyanoplatinate, K₂Pt(CNS)₆

Potassium Thiocyanoplatinate, K₂Pt(CNS)₆, is formed when a warm solution of potassium thiocyanate is added to one of chlor-platinic acid or to a suspension of potassium chlor-platinate in water. It crystallises in red hexagonal prisms, the parameters being:

a: с = 1: 0.7829.

Density 2.342 at 18° C. The dihydrate, K₂Pt(CNS)₆.2H₂O, is known. It yields rhombic crystals:

a:b:c = 0.6224: 1: 0.9712.