Carbon monosulfide

This article is about an unstable molecule and is not to be confused with CS gas, a tear gas; or caesium, an element with symbol Cs.

Carbon monosulfide is a chemical compound with the formula CS. This diatomic molecule is the sulfur analogue of carbon monoxide, and is unstable as a solid or a liquid, but it has been observed as a gas both in the laboratory and in the interstellar medium.^[1] The molecule resembles carbon monoxide with a triple bond between carbon and sulfur. The molecule is not intrinsically unstable, but it tends to polymerize in sunlight to a brown mass, as first discovered in 1868 and 1872.^[2] The polymer is quite stable, decomposing a little at 360 °C to carbon disulfide. This tendency towards polymerization reflects the greater stability of C–S single bonds.

Carbon monosulfide

Names
IUPAC name carbon monosulfide
Other names carbon(II) sulfide, thiocarbonyl, sulfidocarbon, methanidylidynesulfanium
Identifiers
CAS Number	2944-05-0 Y
3D model (JSmol)	Interactive image
Beilstein Reference	1697516, 1918616
ChEBI	CHEBI:30253
ChemSpider	97157 Y
Gmelin Reference	648
PubChem CID	108054
CompTox Dashboard (EPA)	DTXSID00183645
InChI InChI=1S/CS/c1-2 N Key: DXHPZXWIPWDXHJ-UHFFFAOYSA-N N InChI=1/CS/c1-2 Key: DXHPZXWIPWDXHJ-UHFFFAOYAW
SMILES [S+]#[C-]
Properties
Chemical formula	CS
Molar mass	44.07 g·mol−1
Appearance	reddish crystalline powder
Solubility in water	insoluble
Related compounds
Other anions	Carbon monoxide
Other cations	Silicon monosulfide Germanium monosulfide Tin(II) sulfide Lead(II) sulfide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Polymers with the formula (CS)_n have been reported,^[3] and the formal dimer is ethenedithione. Also, CS has been observed as a ligand in some transition metal complexes.^{[citation needed]}

The simplest carbon monosulfide synthesis decomposes carbon disulfide in a high-voltage AC arc.^[4]