Copper monosulfide

Names
IUPAC name

Copper sulfide

Other names

* Covellite
* Copper(II) sulfide
* Cupric sulfide

Identifiers

CAS Number

* 1317-40-4 Y

3D model (JSmol)

* Interactive image

ChemSpider |

* 14145 Y

ECHA InfoCard | 100.013.884
EC Number |

* 215-271-2

PubChem CID

* 14831

RTECS number |

* GL8912000

UNII |

* KL4YU612X7 Y

CompTox Dashboard (EPA)

* DTXSID601316949 DTXSID0061666, DTXSID601316949

InChI

* InChI=1S/Cu.S Y

Key: BWFPGXWASODCHM-UHFFFAOYSA-N Y

* InChI=1/Cu.S/rCuS/c1-2

Key: BWFPGXWASODCHM-BLKBWTQCAT

SMILES

* [Cu]=S

Properties

Chemical formula

| 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)[2]

Solubility in water

| 3.3×10−5 g/100 ml (18 °C)[citation needed]

Solubility product (Ksp)

| 5×10−37[1][need quotation to verify]
Solubility in nitric acid | soluble[citation needed][quantify]
Solubility in ammonium hydroxide | soluble[citation needed][quantify]

Magnetic susceptibility (χ)

| −2.0×10−6 cm3/mol

Refractive index (nD)

| 1.45
Structure

Crystal structure

| hexagonal
Hazards
GHS labelling:

Pictograms

Hazard statements

| H413

Precautionary statements

| P273, P501
NIOSH (US health exposure limits):[3]

PEL (Permissible)

| TWA 1 mg/m3 (as Cu)

REL (Recommended)

| TWA 1 mg/m3 (as Cu)

IDLH (Immediate danger)

| TWA 100 mg/m3 (as Cu)
Related compounds

Other anions

| Copper(II) oxide

Other cations

| zinc sulfide

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Y verify (what is YN ?)

Infobox references

Chemical compound

Copper monosulfide is a chemical compound of copper and sulfur. It was initially thought to occur in nature as the dark indigo blue mineral covellite. However, it was later shown to be a cuprous compound, formula Cu3S(S2).[4][clarification needed] CuS is a moderate conductor of electricity.[5][page needed] A black colloidal precipitate of CuS is formed when hydrogen sulfide, H2S, is bubbled through solutions of Cu(II) salts.[6][page needed] 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[7] and photovoltaics.[8]

## Manufacturing

[edit]

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Copper monosulfide can be prepared by passing hydrogen sulfide gas into a solution of copper(II) 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.

## CuS structure and bonding

[edit]

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[9] 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 (86 °F).[10]
The crystal structure of covellite has been reported several times,[11][12][13] 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[14][page needed] and is quite different from Copper(II) oxide, but similar to Copper(II) selenide (or referred to as Klockmannite). The covellite unit cell contains 6 formula units (12 atoms) in which:

* 4 Cu atoms have tetrahedral coordination (see illustration).
* 2 Cu atoms have trigonal planar coordination (see illustration).
* 2 pairs of S atoms are only 207.1 picometers apart[13] indicating the existence of an S-S bond (a disulfide unit).
* the 2 remaining S atoms form trigonal planar triangles around the copper atoms, and are surrounded by five Cu atoms in a pentagonal bipyramid (see illustration).
* The S atoms at each end of a disulfide unit are tetrahedrally coordinated to 3 tetrahedrally coordinated Cu atoms and the other S atom in the disulfide unit (see illustration).

The formulation of copper sulfide as CuIIS (i.e. containing no sulfur-sulfur bond) is clearly incompatible with the crystal structure, and also at variance with the observed diamagnetism[15][page needed] as a Cu(II) compound would have a d9 configuration and be expected to be paramagnetic.[6][page needed]

Studies using XPS[16][17][18][19] indicate that all of the copper atoms have an oxidation state of +1. This contradicts a formulation based on the crystal structure and obeying the octet rule that is found in many textbooks (e.g.[6][page needed][20][page needed]) describing CuS as containing both CuI and CuII i.e. (Cu+)2Cu2+(S2)2−S2−. An alternative formulation as (Cu+)3(S2−)(S2)− was proposed and supported by calculations. The formulation should not be interpreted as containing radical anion, but rather that there is a delocalized valence "hole".[4][21] Electron paramagnetic resonance studies on the precipitation of Cu(II) salts indicates that the reduction of Cu(II) to Cu(I) occurs in solution.[22]

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ball-and-stick model of part of
the crystal structure of covellite | trigonal planar
coordination of copper | tetrahedral
coordination of copper | trigonal bipyramidal
coordination of sulfur | tetrahedral
coordination of sulfur-note[clarification needed] disulfide unit

## See also

[edit]

* Copper sulfide for an overview of all copper sulfide phases
* Copper(I) sulfide, Cu2S
* Covellite

## References

[edit]

1. ^ Rollie J. Myers (1986). "The new low value for the second dissociation constant for H2S: Its history, its best value, and its impact on the teaching of sulfide equilibria". J. Chem. Educ. 63 (8): 687. Bibcode:1986JChEd..63..687M. doi:10.1021/ed063p687.
2. ^ Blachnik, R.; Müller, A. (2000). "The formation of Cu2S from the elements I. Copper used in form of powders". Thermochimica Acta. 361 (1–2): 31–52\. doi:10.1016/S0040-6031(00)00545-1.1–2&rft.pages=31-52&rft.date=2000&rft_id=info:doi/10.1016/S0040-6031(00)00545-1&rft.aulast=Blachnik&rft.aufirst=R.&rft.au=Müller,+A.&rfr_id=info:sid/en.wikipedia.org:Copper+monosulfide" class="Z3988">
3. ^ "NIOSH Pocket Guide to Chemical Hazards".
4. ^ a b Liang, W.; Whangbo, M.-H. (February 1993). "Conductivity anisotropy and structural phase transition in Covellite CuS". Solid State Communications. 85 (5): 405–408\. doi:10.1016/0038-1098(93)90689-K.
5. ^ Wells, A. F. (1962). Structural Inorganic Chemistry (3rd ed.). Oxford University Press. ISBN 0198553218. `{{cite book}}`: ISBN / Date incompatibility (help)
6. ^ a b c Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
7. ^ Kuchmii, S.Y.; Korzhak A.V.; Raevskaya A.E.; Kryukov A.I. (2001). "Catalysis of the Sodium Sulfide Reduction of Methylviologene by CuS Nanoparticles". Theoretical and Experimental Chemistry. 37 (1). New York: Springer: 36–41\. doi:10.1023/A:1010465823376. S2CID 91893521.
8. ^ Mane, R.S.; Lokhande C.D. (June 2000). "Chemical deposition method for metal chalcogenide thin films". Materials Chemistry and Physics. 65 (1): 1–31\. doi:10.1016/S0254-0584(00)00217-0.
9. ^ Peiris, M; Sweeney, J.S.; Campbell, A.J.; Heinz D. L. (1996). "Pressure-induced amorphization of covellite, CuS". J. Chem. Phys. 104 (1): 11–16\. Bibcode:1996JChPh.104...11P. doi:10.1063/1.470870.
10. ^ Grijalva, H.; Inoue, M.; Boggavarapu, S.; Calvert, P. (1996). "Amorphous and crystalline copper sulfides, CuS". J. Mater. Chem. 6 (7): 1157–1160\. doi:10.1039/JM9960601157.
11. ^ Oftedal, I. (1932). "Die Kristallstruktur des Covellins (CuS)". Z. Kristallogr. 83 (1–6): 9–25\. doi:10.1524/zkri.1932.83.1.9. S2CID 101164006.1–6&rft.pages=9-25&rft.date=1932&rft_id=info:doi/10.1524/zkri.1932.83.1.9&rft_id=https://api.semanticscholar.org/CorpusID:101164006#id-name=S2CID&rft.aulast=Oftedal&rft.aufirst=I.&rfr_id=info:sid/en.wikipedia.org:Copper+monosulfide" class="Z3988">
12. ^ Berry, L. G. (1954). "The crystal structure of covellite CuS and klockmannite CuSe". American Mineralogist. 39: 504.
13. ^ a b Evans, H.T. Jr.; Konnert J. (1976). "Crystal structure refinement of covellite". American Mineralogist. 61: 996–1000.
14. ^ Wells, A. F. (1984). Structural inorganic chemistry (5th ed.). Oxford [Oxfordshire] : New York: Clarendon Press ; Oxford University Press. ISBN 0-19-855370-6.
15. ^ Magnetic susceptibility of the elements and inorganic compounds Archived 2012-01-12 at the Wayback Machine
16. ^ Nakai, I.; Sugitani, Y.; Nagashima, K.; Niwa, Y. (1978). "X-ray photoelectron spectroscopic study of copper minerals". Journal of Inorganic and Nuclear Chemistry. 40 (5): 789–791\. doi:10.1016/0022-1902(78)80152-3.
17. ^ Folmer, J.C.W.; Jellinek F. (1980). "The valence of copper in sulfides and selenides: An X-ray photoelectron spectroscopy study". Journal of the Less Common Metals. 76 (1–2): 789–791\. doi:10.1016/0022-5088(80)90019-3.1–2&rft.pages=789-791&rft.date=1980&rft_id=info:doi/10.1016/0022-5088(80)90019-3&rft.aulast=Folmer&rft.aufirst=J.C.W.&rft.au=Jellinek+F.&rfr_id=info:sid/en.wikipedia.org:Copper+monosulfide" class="Z3988">
18. ^ Folmer, J.C.W.; Jellinek F.; Calis G.H.M (1988). "The electronic structure of pyrites, particularly CuS2 and Fe1−xCuxSe2: An XPS and Mössbauer study". Journal of Solid State Chemistry. 72 (1): 137–144\. Bibcode:1988JSSCh..72..137F. doi:10.1016/0022-4596(88)90017-5.
19. ^ Goh, S.W.; Buckley A.N.; Lamb R.N. (February 2006). "Copper(II) sulfide?". Minerals Engineering. 19 (2): 204–208\. doi:10.1016/j.mineng.2005.09.003.
20. ^ Cotton, F. Albert; Wilkinson, Geoffrey; Murillo, Carlos A.; Bochmann, Manfred (1999), Advanced Inorganic Chemistry (6th ed.), New York: Wiley-Interscience, ISBN 0-471-19957-5
21. ^ Nozaki, H; Shibata, K; Ohhashi,N. (April 1991). "Metallic hole conduction in CuS". Journal of Solid State Chemistry. 91 (2): 306–311\. Bibcode:1991JSSCh..91..306N. doi:10.1016/0022-4596(91)90085-V.
22. ^ Luther, GW; Theberge SM; Rozan TF; Rickard D; Rowlands CC; Oldroyd A. (February 2002). "Aqueous copper sulfide clusters as intermediates during copper sulfide formation". Environ. Sci. Technol. 36 (3): 394–402\. Bibcode:2002EnST...36..394L. doi:10.1021/es010906k. PMID 11871554.

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* t
* e

Copper compounds

Cu(0,I)|

* Cu5Si

Cu(I)|

* CuBr
* CuCN
* CuCl
* CuF
* CuH
* CuI
* Cu2C2
* Cu2Cr2O5
* Cu2O
* CuOH
* CuNO3
* Cu3P
* Cu2S
* CuSCN
* C6H5Cu

Cu(I,II)|

* Cu4O3
* Cu3H4O8S2

Cu(II)|

* Cu(BF4)2
* CuBr2
* CuC2
* Cu(CH3COO)2
* Cu(CF3COO)2
* Cu(C3H5O3)2
* CuCO3
* Cu2CO3(OH)2
* Cu(CN)2
* CuCl2 / KCuCl3 / K2CuCl4
* Cu(ClO3)2
* Cu(ClO4)2
* CuF2
* Cu(NO3)2
* Cu3(PO4)2
* Cu3(BO3)2
* Cu(N3)2
* CuC2O4
* CuO
* CuO2
* Cu(OH)2
* CuS
* Cu(SCN)2
* CuSO4
* Cu3(AsO4)2
* Cu(C
11H
23COO)

* Cu(C17H35COO)2
* Cu(O2CC6H5)2
* CuTe
* CuTe2

Cu(III)|

* K3CuF6
* CuO−

Cu(IV)|

* CuO2
* Cs2CuF6

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* e

Sulfides (S2−)

| H2S |  |  |  | He

|
|
|
|

Li2S | BeS | B2S3
+BO3 | CS2
COS | (NH4)SH | O  | F  | Ne
Na2S | MgS | Al2S3 | SiS
SiS2
-Si | PxSy
-P | -S2−
2 | Cl  | Ar
K2S | CaS |  | ScS
Sc2S3 | TiS
TiS2
Ti2S3 | VS
VS2
V2S3 | CrS
Cr2S3 | MnS
MnS2 | FeS
Fe3S4 | CoxSy | NixSy | Cu2S
CuS | ZnS | GaS
Ga2S3 | GeS
GeS2
-Ge | As2S3
As2S5
As4S3
-As | SeS2
+Se | Br  | Kr
Rb2S | SrS |  | Y2S3 | ZrS2 | NbS2 | MoS2
MoS3 | TcS2
Tc2S7 | Ru  | Rh2S3 | PdS | Ag2S | CdS | In2S3 | SnS
SnS2
-Sn | Sb2S3
Sb2S5
-Sb | TeS2 | I  | Xe
Cs2S | BaS | *  | LuS
Lu2S3 | HfS2 | TaS2 | WS2
WS3 | ReS2
Re2S7 | OsS
4 | Ir2S3
IrS2 | PtS
PtS2 | Au2S
Au2S3 | HgS | Tl2S | PbS
PbS2 | Bi2S3 | PoS | At  | Rn
Fr  | Ra  | **  | Lr  | Rf  | Db  | Sg  | Bh  | Hs  | Mt  | Ds  | Rg  | Cn  | Nh  | Fl  | Mc  | Lv  | Ts  | Og

*  | LaS
La2S3 | CeS
Ce2S3 | PrS
Pr2S3 | NdS
Nd2S3 | PmS
Pm2S3 | SmS
Sm2S3 | EuS
Eu2S3 | GdS
Gd2S3 | TbS
Tb2S3 | DyS
Dy2S3 | HoS
Ho2S3 | ErS
Er2S3 | TmS
Tm2S3 | YbS
Yb2S3
**  | Ac2S3 | ThS
Th2S3
Th7S12
ThS2 | Pa  | US
U2S3
U3S5
US2 | NpS
Np2S3
Np3S5
NpS2 | PuS
Pu2S3 | AmS
Am2S3 | CmS
Cm2S3 | Bk2S3 | Cf2S3 | Es  | Fm  | Md  | No

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Disulfides (S2−
2) and polysulfides

| H2S2 |  |  |  | He

|
|
|
|

Li  | Be  | B8S16 | RS2R' | N  | S2O | S2F2 | Ne
Na2Sx | Mg  | Al  | Si  | P  | S3 | S2Cl2 | Ar
K  | Ca  |  | Sc  | TiS3 | VS4 | Cr  | MnS2 | FeS2 | CoS2 | NiS2 | "CuS"  | Zn  | Ga  | Ge  | As  | Se  | S2Br2 | Kr
Rb  | Sr  |  | Y  | Zr  | Nb  | Mo  | Tc  | RuS2 | Rh  | Pd  | Ag  | Cd  | In  | Sn  | Sb2S5?  | Te  | S2I2 | Xe
Cs  | Ba  | *  | Lu  | Hf  | Ta  | W  | Re  | Os  | Ir  | Pt  | Au  | Hg  | Tl  | Pb  | Bi  | Po  | At  | Rn
Fr  | Ra  | **  | Lr  | Rf  | Db  | Sg  | Bh  | Hs  | Mt  | Ds  | Rg  | Cn  | Nh  | Fl  | Mc  | Lv  | Ts  | Og

*  | La  | Ce  | Pr  | Nd  | Pm  | Sm  | Eu  | Gd  | Tb  | Dy  | Ho  | Er  | Tm  | Yb
**  | Ac  | Th2S5 | Pa  | U2S5
US3 | Np2S5
NpS3 | PuS2 | AmS2 | CmS2 | BkS2 | CfS2 | Es  | Fm  | Md  | No
*[CID]: Compound ID
*[EPA]: U.S. Environmental Protection Agency
*[H413]: H413: May cause long lasting harmful effects to aquatic life
*[P273]: P273: Avoid release to the environment.
*[P501]: P501: Dispose of contents/container to ...
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