Thiotrithiazyl Iodide, N₃S₄I

Thiotrithiazyl Iodide, N₃S₄I, may be prepared by dissolving thiotrithiazyl chloride in ice-cold water and adding excess of an ice-cold solution of potassium iodide. It is also formed by the action of iodine dissolved in methyl alcohol on thiotrithiazyl chloride, but prepared in this way it is invariably contaminated with chlorine. It is a dark red crystalline powder which decomposes spontaneously with evolution of iodine on exposure to air.