Selenium hexasulfide

Selenium hexasulfide^[1]
Names
	Other names Diselenium hexasulfide
Identifiers
CAS Number	75926-26-0 ;
3D model (JSmol)	1,2: Interactive image; 1,5: Interactive image;
ChemSpider	1,2: 9296780; 1,5: 9057901;
PubChem CID	1,2: 11121651; 1,5: 10882632;
	InChI 1,2: InChI=1S/S6Se2/c1-2-4-6-8-7-5-3-1 Key: GVMSZJKNEHYJTG-UHFFFAOYSA-N; 1,5: InChI=1S/S6Se2/c1-3-7-5-2-6-8-4-1 Key: XHXZYRZXIYIDIG-UHFFFAOYSA-N;
	SMILES 1,2: S1SSS[Se][Se]SS1; 1,5: S1S[Se]SSS[Se]S1;
Properties
Chemical formula	Se2S6
Molar mass	350.32 g/mol
Appearance	orange needles
Density	2.44 g/cm3
Melting point	121.5 °C (250.7 °F; 394.6 K)
Solubility	soluble in carbon disulfide
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Selenium hexasulfide is a chemical compound with formula Se₂S₆. Its molecular structure consists of a ring of two selenium and six sulfur atoms, analogous to the S₈ allotrope of sulfur (cyclooctasulfur) and other selenium sulfides with formula Se_nS_8−n.^[2]

There are several isomers depending on the relative placement of the selenium atoms in the ring: 1,2 (with the two Se atoms adjacent), 1,3, 1,4, and 1,5 (with the Se atoms opposite).^[3] It is an oxidizing agent.

The 1,2 isomer can be prepared by reaction of chlorosulfanes and dichlorodiselane with potassium iodide in carbon disulfide. The reaction produces also cyclooctaselenium Se₈ and all other eight-member cyclic selenium sulfides, except SeS₇, and several six- and seven-membered rings. ^[2]

References

^ Lide, David R. (1998), Handbook of Chemistry and Physics (87 ed.), Boca Raton, Florida: CRC Press, pp. 4–81, ISBN 0-8493-0594-2
^ ^a ^b Risto S. Laitinen, Pentti Pekone, Yrjö Hiltunen and Tapanin A. Pakkanen (1989), "The 77s NMR spestroscopic Identification of Heterocyclic Selenium Sulfides Prepared by the Reactions of Chlorosulfanes and Dichlorodiselane with Potassium Iodide". Acta Chemica Scandinavica, volume 43, pages 436-440.
^ Arto Maaninen, Tristram Chivers, Masood Parvez, Jarkko Pietikäinen, and Risto S. Laitinen (1999), "Syntheses of THF Solutions of SeX₂ (X = Cl, Br) and a New Route to Selenium Sulfides Se_nS_8−n (n = 1−5): X-ray Crystal Structures of SeCl₂(tht)₂ and SeCl₂·tmtu". Inorganic Chemistry, volume 38, issue 18, pages 4093–4097 doi:10.1021/ic981430h

[hand-1] Lide, David R. (1998), Handbook of Chemistry and Physics (87 ed.), Boca Raton, Florida: CRC Press, pp. 4–81, ISBN 0-8493-0594-2

[laitinen-2] Risto S. Laitinen, Pentti Pekone, Yrjö Hiltunen and Tapanin A. Pakkanen (1989), "The 77s NMR spestroscopic Identification of Heterocyclic Selenium Sulfides Prepared by the Reactions of Chlorosulfanes and Dichlorodiselane with Potassium Iodide". Acta Chemica Scandinavica, volume 43, pages 436-440.

[maan-3] Arto Maaninen, Tristram Chivers, Masood Parvez, Jarkko Pietikäinen, and Risto S. Laitinen (1999), "Syntheses of THF Solutions of SeX₂ (X = Cl, Br) and a New Route to Selenium Sulfides Se_nS_8−n (n = 1−5): X-ray Crystal Structures of SeCl₂(tht)₂ and SeCl₂·tmtu". Inorganic Chemistry, volume 38, issue 18, pages 4093–4097 doi:10.1021/ic981430h

[1]

[2]

[3]

Names
Other names Diselenium hexasulfide
Identifiers
CAS Number	75926-26-0
3D model (JSmol)	1,2: Interactive image 1,5: Interactive image
ChemSpider	1,2: 9296780 1,5: 9057901
PubChem CID	1,2: 11121651 1,5: 10882632
InChI 1,2: InChI=1S/S6Se2/c1-2-4-6-8-7-5-3-1 Key: GVMSZJKNEHYJTG-UHFFFAOYSA-N 1,5: InChI=1S/S6Se2/c1-3-7-5-2-6-8-4-1 Key: XHXZYRZXIYIDIG-UHFFFAOYSA-N
SMILES 1,2: S1SSS[Se][Se]SS1 1,5: S1S[Se]SSS[Se]S1
Properties
Chemical formula	Se₂S₆
Molar mass	350.32 g/mol
Appearance	orange needles
Density	2.44 g/cm³
Melting point	121.5 °C (250.7 °F; 394.6 K)
Solubility	soluble in carbon disulfide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).