Diphosphorus Trisulphide, P₂S₃

Diphosphorus Trisulphide or Phosphorus Tetritahexasulphide, P₂S₃ or P₄S₆.—The preparation of a compound of this composition by heating the constituent elements in the correct proportions was reported by the earlier workers. It was described as a yellowish-white substance which could be obtained as a sublimate and purified by sublimation. It gave a vapour the density of which corresponded to P₄S₆. When hydrogen sulphide is caused to react with phosphorus trihalides the solid remaining has the composition P₂S₃.

The substance melted at 290° C., 296° C. It sublimed between 490° and 550° C. It did not fume or glow in the air, but in other respects its chemical properties resembled those of P₄S₃.