Antimony pentasulfide is an inorganic compound of antimony and sulfur, also known as antimony red. It is a nonstoichiometric compound with a variable composition. Commercial samples are usually are contaminated with sulfur, which may be removed by washing with carbon disulfide in a Soxhlet extractor. It may be used as a red pigment and is one possible precursor to Schlippe's Salt, Na3SbS4, which can be prepared according to the equation:
- 3 Na2S + Sb2S5 + 9 H2O → 2 Na3SbS4·9H2O
Like many sulfides, this compound liberates hydrogen sulfide upon treatment with strong acids like hydrochloric acid.
- 6 HCl + Sb2S5 → 2 SbCl3 + 3 H2S + 2 S
Analysis by Mössbauer spectroscopy indicates that this compound is a derivative antimony(III), explaining the production of antimony(III) chloride, rather than antimony(V) chloride, upon acidification. It is therefore not analogous to the phosphorus(V) compound phosphorus pentasulfide.
- ^ Strem MSDS
- ^ G. G. Long, J. G. Stevens, L. H. Bowen, S. L. Ruby (1969). "The oxidation number of antimony in antimony pentasulfide". Inorganic and Nuclear Chemistry Letters 5 (1): 21–25. doi:10.1016/0020-1650(69)80231-X.