Tin(II) sulfide Tin(II) sulfide Tin(II) sulfide is a chemical compound of tin and sulfur. The chemical formula is SnS. Its natural occurrence concerns herzenbergite (α-SnS), a rare mineral. At elevated temperatures above 905K, SnS undergoes a second order phase transition to β-SnS (space group: cmcm, No. 63). in recent years, it has become evident that a new polymorph of SnS exist based upon the cubic crystal system, π-SnS (space group: P23, No. 198). Tin(II) sulfide can be prepared by reacting tin with sulfur, or tin(II) chloride with hydrogen sulfide. Tin(II) sulfide is a dark brown or black solid, insoluble in water, but
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