Palladium Subsulphide, Pd₂S

Palladium Subsulphide, Pd₂S has been prepared by heating to bright redness a mixture of palladous sulphide (1 part) with ammonium chloride (6 parts), sodium hydroxide (12 parts), and flowers of sulphur (12 parts). The product is washed with cold water.

Another method consists in igniting palladosammine chloride, PdCl₂.2NH₃, with 25 per cent, of its weight of sulphur in a crucible under a layer of borax, at the temperature at which gold melts (circa 1062° C.).

As obtained by these methods palladium subsulphide is a hard, grey, metallic-looking mass, with a granular fracture. It is amorphous; density 7.3; and it is soluble in aqua regia.