Chromium(III) sulfide is the inorganic compound with the formula Cr<sub>2</sub>S<sub>3</sub>. It is a brown-black solid. Chromium sulfides are usually nonstoichiometric compounds, with formulas ranging from CrS to Cr<sub>0.67</sub>S (corresponding to Cr<sub>2</sub>S<sub>3</sub>).
Chromium(III) sulfide can be prepared through the reaction of a stoichiometric mixture of the elements at 1000 ðC
It is a solid that is insoluble in water. According to X-ray crystallography, its structure is a combination of that of nickel arsenide (1:1 stoichiometry) and Cd(OH)<sub>2</sub> (1:2 stoichiometry). Some metal-metal bonding is indicated by the short Cr-Cr distance of 2.78 ÃÂ .