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Phosphorus pentasulfide
General
Other names	phosphorus sulfide sulfur phosphide phosphorus persulfide diphosphorus pentasulfide tetraphosphorus decasulfide
Molecular formula	P4S10
Empirical formula	P2S5
Molar mass	444.555 g mol−1
Appearance	yellow solid
CAS number	[1314-80-3]
Properties
Density and phase	2.09 g cm−3, solid
Solubility in water	hydrolyses
Solubility in other solvents	0.222 g / 100g CS2 (at 17 °C) Soluble in C6H6
Melting point	288 °C (561 K)
Boiling point	514 °C (787 K)
Vapor pressure
Hazards
EU classification
NFPA 704
Related compounds	P4S3
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Phosphorus pentasulfide is the chemical compound with the formula P₄S₁₀. This yellow solid is an industrially important inorganic compound of phosphorus and sulfur. Commercial samples often appear greenish-gray. The compound is soluble in carbon disulfide and benzene, but it reacts with most organic compounds. Its molecular structure is related to that of adamantane, a common motif in inorganic chemistry, and is almost identical to the structure of phosphorus pentoxide.^[1]

Contents 1 Production 2 Reactivity 3 Related phosphorus sulfides 4 Applications 5 References 6 External links

Phosphorus pentasulfide is obtained by the reaction of liquid white phosphorus, P₄, with sulfur above 300 °C. Alternatively, P₄S₁₀ can be formed by reacting elemental sulfur or pyrite, FeS₂, with ferrophosphorus, impure Fe₂P (a byproduct of P₄ production from phosphate rock):

4Fe₂P + 18S → P₄S₁₀ + 8FeS

4Fe₂P + 18FeS₂ + heat → P₄S₁₀ + 26FeS

Due to hydrolysis by atmospheric moisture, P₄S₁₀ evolves H₂S, thus P₄S₁₀ is associated with a rotten egg odour. Aside from H₂S, hydrolysis of P₄S₁₀ gives phosphoric acid:

P₄S₁₀ + 16H₂O → 4H₃PO₄ + 10H₂S

Other mild nucleophiles react with P₄S₁₀, including alcohols and amines.

Aside from the commercially important P₄S₃ and P₄S₁₀, several other phosphorus sulfides are known with the formula P₄S_x where x is less than or equal to 10. Six of these phosphorus sulfides exist as isomers: P₄S₄, P₄S₅, P₄S₆, P₄S₇, P₄S₈, and P₄S₉. These isomers are distinguished by Greek letter prefixes. The prefix is based on the order of the discovery of the isomers, not on structural principles.^[2] All known molecular phosphorus sulfides contain a tetrahedral array of four phosphorus atoms.

The main method for preparing these compounds is thermolysis of mixtures of phosphorus and sulfur. The product distributions can be analyzed by ³¹P NMR spectroscopy. More selective syntheses entail (i) desulfurization, e.g. using triphenylphosphine and, complementarily, (ii) sulfidation using triphenylarsine sulfide.^[3][4]

Phosphorus pentasulfide is used for manufacturing zinc dialkyl dithio phosphate, insecticides, ore flotation agents, and various organophosphates. It is also a component of some amorphous solid electrolytes (eg. Li₂S-P₂S₅) for some types of lithium batteries.

Phosphorus pentasulfide is a dual-use material, as it can be used for manufacture of the VX nerve agent.

1. ^ D. E. C. Corbridge "Phosphorus: An Outline of its Chemistry, Biochemistry, and Technology" 5th Edition Elsevier: Amsterdam 1995. ISBN 0-444-89307-5.
2. ^ Jason, M. E.; Ngo, T.; Rahman, S. ”Products and Mechanisms in the Oxidation of Phosphorus by Sulfur at Low Temperature” Inorganic Chemistry 1997, volume 36, pages 2633-2640. DOI: 10.1021/ic9614879
3. ^ Jason, M. E. “Transfer of Sulfur from Arsenic and Antimony Sulfides to Phosphorus Sulfides. Rational Syntheses of Several Less-Common P₄S_n Species” Inorganic Chemistry 1997, volume 36, pages 2641-2646. DOI:10.1021/ic9614881 10.1021/ic9614881.
4. ^ Nowottnick, H.; Blachnik, R. "Zwei neue Phosphorsulfide” (Two New Phosphorus Sulfides) Zeitschrift für Anorganische und Allgemeine Chemie 1999, volume 625, pages 1966-1968. DOI:ISSN:0044-2313. ZAACAB ISSN:0044-2313.

• Links to external chemical sources