Copper(II) sulfide
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| Names | |
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IUPAC name
Copper sulfide
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| Other names | |
| Identifiers | |
1317-40-4 
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| 3D model (Jmol) | Interactive image |
| ChemSpider |
14145
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| ECHA InfoCard | 100.013.884 |
| PubChem | 14831 |
| RTECS number | GL8912000 |
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| Properties | |
| CuS | |
| Molar mass | 95.611 g/mol |
| Appearance | black powder or lumps |
| Density | 4.76 g/cm3 |
| Melting point | above 500 °C (932 °F; 773 K) (decomposes) |
| 0.000033 g/100 mL (18 °C) | |
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Solubility product (Ksp)
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6 x 10−37 |
| Solubility | soluble in HNO3, NH4OH, KCN insoluble in HCl, H2SO4 |
| -2.0·10−6 cm3/mol | |
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Refractive index (nD)
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1.45 |
| Structure | |
| hexagonal | |
| Hazards | |
| US health exposure limits (NIOSH): | |
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PEL (Permissible)
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TWA 1 mg/m3 (as Cu) |
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REL (Recommended)
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TWA 1 mg/m3 (as Cu) |
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IDLH (Immediate danger)
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TWA 100 mg/m3 (as Cu) |
| Related compounds | |
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Other anions
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Copper(II) oxide |
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Other cations
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zinc sulfide |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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 (what is  ?) |
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| Infobox references | |
Copper sulfide is a chemical compound of copper and sulfur. It occurs in nature as the dark indigo blue mineral covellite. It is a moderate conductor of electricity. A black colloidal precipitate of CuS is formed when hydrogen sulfide, H2S, is bubbled through solutions of Cu(II) salts. It is one of a number of binary compounds of copper and sulfur (see copper sulfide for an overview of this subject), and has attracted interest because of its potential uses in catalysis and photovoltaics.
Copper sulfide can be prepared by passing hydrogen sulfide gas into a solution of copper salt.
Alternatively, it can be prepared by melting an excess of sulfur with copper(I) sulfide or by precipitation with hydrogen sulfide from a solution of anhydrous copper(II) chloride in anhydrous ethanol.
The reaction of copper with molten sulfur followed by boiling sodium hydroxide and the reaction of sodium sulfide with aqueous copper sulfate will also produce copper sulfide.
Copper sulfide crystallizes in the hexagonal crystal system, and this is the form of the mineral covellite. There is also an amorphous high pressure form which on the basis of the Raman spectrum has been described as having a distorted covellite structure. An amorphous room temperature semiconducting form produced by the reaction of a Cu(II) ethylenediamine complex with thiourea has been reported, which transforms to the crystalline covellite form at 30 °C.
The crystal structure of covellite has been reported several times, and whilst these studies are in general agreement on assigning the space group P63/mmc there are small discrepancies in bond lengths and angles between them. The structure was described as "extraordinary" by Wells and is quite different from copper(II) oxide, but similar to CuSe (klockmannite). The covellite unit cell contains 6 formula units (12 atoms)in which:
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