Disulfur monoxide or sulfur suboxide is an inorganic compound with formula S2O. It is one of the lower sulfur oxides. It is a colourless gas and condenses to give a pale coloured solid that is unstable at room temperature. It is a bent molecule with an S−S−O angle of 117.88°, S−S bond length of 188.4 pm, and S−O bond length of 146.5 pm.
sulfur suboxide; sulfuroxide;
3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||80.1294 g/mol|
|Appearance||colourless gas or dark red solid|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
- 3 S8 + 12 CuO → 12 CuS + 4 S2O + 4 SO2
- SOCl2 + Ag2S → 2 AgCl + S2O
Disulfur monoxide forms a yellow solution in carbon tetrachloride. The solid can be obtained at liquid nitrogen temperatures, often appearing dark-colored owing to impurities. On decomposition at room temperature it forms SO2 via the formation of polysulfur oxides.
Disulfur monoxide was first produced by P. W. Schenk in 1933 with a glow discharge though sulfur vapour and sulfur dioxide. He discovered that the gas could survive for hours at single digit pressures of mercury in clean glass, but decomposed near 30 mmHg (4 kPa). Schenk assigned the formula as SO and called it sulfur monoxide. In 1940, K. Kondratyeva and V. Kondratyev proposed the formula as S2O2, disulfur dioxide. In 1956, D. J. Meschi and R. J. Myers established the formula as S2O.
The bacterium Desulfovibrio desulfuricans is claimed to produce S2O. S2O can be found coming from volcanoes on Io. It can form between 1% and 6% when hot 100-bar S2 and SO2 gas erupts from volcanoes. It is believed that Pele on Io is surrounded by solid S2O.
In the ultraviolet S2O has absorption band systems in the ranges 250–340 nm and 190–240 nm. There are bands at 323.5 and 327.8 nm. The band in the 315–340 nm range is due to the C1A′–X1A′ (π* ← π) transition.
- 2 S2O → S3 + SO2
Disulfur monoxide is a ligand bound to transition metals. These are formed by oxidation peroxide oxidation of a disulfur ligand. Excessive oxygen can yield a dioxygendisulfur ligand, which can be reduced in turn with triphenylphosphine. Examples are: [Ir(dppe)2S2O]+, OsCl(NO)(PPh3)2S2O, NbCl(η-C5H5)2S2O, Mn(CO)2(η-C5Me5)S2O, Re(CO)2(η-C5Me5)S2O, Re(CO)2(η-C5H5)S2O.
The molybdenum compound Mo(CO)2(S2CNEt2)2 reacts with elemental sulfur and air to form a compound Mo2(S2O)2(S2CNEt2)4. Another way to form these complexes is to combine sulfonyliminooxo-λ4-sulfurane (OSNSO2·R) complexes with hydrogen sulfide. Complexes formed in this way are: IrCl(CO)(PPh3)2S2O; Mn(CO)2(η-C5H5)S2O. With hydrosulfide and a base followed by oxygen, OsCl(NO)(PPh3)2S2O can be made.
Cyclic disulfur monoxide has been made from S2O by irradiating the solid in an inert gas matrix with 308 nm ultraviolet light.
- "Disulfur monoxide". NIST. 2008.
- Hapke, B.; Graham, F. (May 1989). "Spectral properties of condensed phases of disulfur monoxide, polysulfur oxide, and irradiated sulfur". Icarus. 79 (1): 47. Bibcode:1989Icar...79...47H. doi:10.1016/0019-1035(89)90107-3.
- Steudel, R. (2003). "Sulfur-Rich Oxides SnO and SnO2". In Steudel, R. (ed.). Elemental Sulfur and Sulfur-Rich Compounds II. Berlin/Heidelberg: Springer. ISBN 9783540449515.
- Meschi, D. J.; Myers, R. J. (1959). "The microwave spectrum, structure, and dipole moment of disulfur monoxide". Journal of Molecular Spectroscopy. 3 (1–6): 405–416. Bibcode:1959JMoSp...3..405M. doi:10.1016/0022-2852(59)90036-0.
- Schenk, Peter W. (18 March 1933). "Über das Schwefelmonoxyd" [On sulfur monoxide]. Zeitschrift für Anorganische und Allgemeine Chemie (in German). 211 (1–2): 150–160. doi:10.1002/zaac.19332110117.
- Hallin, K-E. J.; Merer, A. J.; Milton, D. J. (November 1977). "Rotational analysis of bands of the 3400 Å system of disulphur monoxide (S2O)". Canadian Journal of Physics. 55 (21): 1858–1867. Bibcode:1977CaJPh..55.1858H. doi:10.1139/p77-226.
- Satyanarayana, S. R.; Vasudeva Murthy, A. R. (1964). "Reactions with Disulphur monoxide Solutions Obtained by the Reduction of Cupric Oxide by Elemental Sulphur" (PDF). Proceedings of the Indian Academy of Sciences, Section A. 59 (4).
- Cotton and Wilkinson (1966). Advanced Inorganic Chemistry: A Comprehensive Treatise. p. 540.
- Meschi, David J.; Myers, Rollie J. (30 July 1956). "Disulfur Monoxide. I. Its Identification as the Major Constituent in Schenk's "Sulfur Monoxide"". Journal of the American Chemical Society. 78 (24): 6220. doi:10.1021/ja01605a002.
- Iverson, W. P. (26 May 1967). "Disulfur monoxide: production by Desulfovibrio". Science. 156 (3778): 1112–1114. Bibcode:1967Sci...156.1112I. doi:10.1126/science.156.3778.1112. PMID 6024190.
- Zolotov, Mikhail Yu.; Fegley, Bruce (9 March 1998). "Volcanic Origin of Disulfur Monoxide (S2O) on Io" (PDF). Icarus. 133 (2): 293. Bibcode:1998Icar..133..293Z. doi:10.1006/icar.1998.5930.
- Cook, Robert L; Winnewisser, Gisbert; Lindsey, D.C (May 1973). "The centrifugal distortion constants of disulfur monoxide". Journal of Molecular Spectroscopy. 46 (2): 276–284. Bibcode:1973JMoSp..46..276C. doi:10.1016/0022-2852(73)90042-8.
- Zhang, Qingguo; Dupré, Patrick; Grzybowski, Bartosz; Vaccaro, Patrick H. (1995). "Laser-induced fluorescence studies of jet-cooled S2O: Axis-switching and predissociation effects". The Journal of Chemical Physics. 103 (1): 67. Bibcode:1995JChPh.103...67Z. doi:10.1063/1.469623.
- Nakayama, J.; Aoki, S.; Takayama, J.; Sakamoto, A.; Sugihara, Y.; Ishii, A. (28 July 2004). "Reversible disulfur monoxide (S2O)-forming retro-Diels–Alder reaction. disproportionation of S2O to trithio-ozone (S3) and sulfur dioxide (SO2) and reactivities of S2O and S3". Journal of the American Chemical Society. 126 (29): 9085–9093. doi:10.1021/ja047729i. PMID 15264842.
- Ishii, A.; Kawai, T.; Tekura, K.; Oshida, H.; Nakayama, J. (18 May 2001). "A Convenient Method for the Generation of a Disulfur Monoxide Equivalent and Its Reaction with Diazoalkanes to Yield Dithiirane 1-Oxides". Angewandte Chemie International Edition. 40 (10): 1924–1926. doi:10.1002/1521-3773(20010518)40:10<1924::AID-ANIE1924>3.0.CO;2-F. PMID 11385674.
- Stone, F. G. A. (7 March 1994). Advances in Organometallic Chemistry. 36. p. 168. ISBN 978-0-12-031136-1.
- Lo, Wen-Jui; Wu, Yu-Jong; Lee, Yuan-Pern (September 2003). "Ultraviolet Absorption Spectrum of Cyclic S2O in Solid Ar". The Journal of Physical Chemistry A. 107 (36): 6944–6947. Bibcode:2003JPCA..107.6944L. doi:10.1021/jp034563j.
|Wikimedia Commons has media related to Disulfur monoxide.|