Copper monosulfide
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IUPAC name
Copper sulfide
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Other names | |
Identifiers | |
3D model (JSmol)
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ChemSpider | |
ECHA InfoCard | 100.013.884 |
EC Number |
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PubChemCID
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RTECS number |
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UNII | |
CompTox Dashboard(EPA)
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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)[2] |
0.000033 g/100 ml (18 °C) | |
Solubility product(Ksp)
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6 x 10−37[1] |
Solubility | soluble inHNO3,NH4OH,KCN insoluble inHCl,H2SO4 |
-2.0·10−6cm3/mol | |
Refractive index(nD)
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1.45 |
Structure | |
hexagonal | |
Hazards | |
GHSlabelling: | |
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H413 | |
P273,P501 | |
NIOSH(US health exposure limits): | |
PEL(Permissible)
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TWA 1 mg/m3(as Cu)[3] |
REL(Recommended)
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TWA 1 mg/m3(as Cu)[3] |
IDLH(Immediate danger)
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TWA 100 mg/m3(as Cu)[3] |
Related compounds | |
Otheranions
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Copper(II) oxide |
Othercations
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zinc sulfide |
Except where otherwise noted, data are given for materials in theirstandard state(at 25 °C [77 °F], 100 kPa).
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Copper monosulfideis achemical compoundofcopperandsulfur.It was initially thought to occur in nature as the dark indigo blue mineralcovellite.However, it was later shown to be rather a cuprous compound, formulaCu3S(S2).[4]CuS is a moderate conductor of electricity.[5]A black colloidal precipitate of CuS is formed whenhydrogen sulfide,H2S, is bubbled through solutions of Cu(II) salts.[6]It is one of a number of binary compounds of copper and sulfur (seecopper sulfidefor an overview of this subject), and has attracted interest because of its potential uses in catalysis[7]andphotovoltaics.[8]
Manufacturing
[edit]Copper monosulfide can be prepared by passinghydrogen sulfidegas into a solution ofcopper(II)salt.
Alternatively, it can be prepared by melting an excess ofsulfurwithcopper(I) sulfideor by precipitation with hydrogen sulfide from a solution of anhydrouscopper(II) chloridein anhydrousethanol.
The reaction of copper with molten sulfur followed by boilingsodium hydroxideand the reaction ofsodium sulfidewith aqueouscopper sulfatewill also produce copper sulfide.
CuS structure and bonding
[edit]Copper sulfide crystallizes in the hexagonal crystal system, and this is the form of the mineralcovellite.There is also an amorphous high pressure form[9]which on the basis of theRaman spectrumhas been described as having a distorted covellite structure. An amorphous room temperature semiconducting form produced by the reaction of a Cu(II)ethylenediaminecomplex withthioureahas been reported, which transforms to the crystalline covellite form at 30 °C.[10]
The crystal structure of covellite has been reported several times,[11][12][13]and whilst these studies are in general agreement on assigning thespace groupP63/mmc there are small discrepancies in bond lengths and angles between them. The structure was described as "extraordinary" by Wells[14]and is quite different fromcopper(II) oxide,but similar toCuSe(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 pm 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]as a Cu(II) compound would have a d9configuration and be expected to be paramagnetic.[6]
Studies usingXPS[16][17][18][19]indicate thatallof the copper atoms have an oxidation state of +1. This contradicts a formulation based on the crystal structure and obeying theoctet rulethat is found in many textbooks (e.g.[6][20]) describing CuS as containing both CuIand CuIIi.e. (Cu+)2Cu2+(S2)2−S2−.An alternative formulation as (Cu+)3(S2−)(S2)−was proposed and supported by calculations.[21]
The formulation should not be interpreted as containing radical anion, but rather that there is a delocalized valence "hole".[21][22]
Electron paramagnetic resonancestudies on the precipitation of Cu(II) salts indicates that the reduction of Cu(II) to Cu(I) occurs in solution.[23]
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ball-and-stick modelof part of the crystal structure ofcovellite |
trigonal planar coordination of copper |
tetrahedral coordination of copper |
trigonal bipyramidal coordination of sulfur |
tetrahedral coordination of sulfur-note disulfide unit |
See also
[edit]- Copper sulfidefor an overview of all copper sulfide phases
- Copper(I) sulfide,Cu2S
- Covellite
References
[edit]- ^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.
- ^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.
- ^abcNIOSH Pocket Guide to Chemical Hazards."#0150".National Institute for Occupational Safety and Health(NIOSH).
- ^Liang, W., Whangbo, M.H. (1993)Conductivity anisotropy and structural phase transition in Covellite CuSSolid State Communications, 85(5), 405-408
- ^Wells A.F. (1962)Structural Inorganic Chemistry3d edition Oxford University Press
- ^abcGreenwood, Norman N.;Earnshaw, Alan (1997).Chemistry of the Elements(2nd ed.).Butterworth-Heinemann.ISBN978-0-08-037941-8.
- ^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.S2CID91893521.
- ^ 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.
- ^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.
- ^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.
- ^Oftedal, I. (1932). "Die Kristallstruktur des Covellins (CuS)".Z. Kristallogr.83(1–6): 9–25.doi:10.1524/zkri.1932.83.1.9.S2CID101164006.
- ^Berry, L. G. (1954). "The crystal structure of covellite CuS and klockmannite CuSe".American Mineralogist.39:504.
- ^abEvans, H.T. Jr.; Konnert J. (1976). "Crystal structure refinement of covellite".American Mineralogist.61:996–1000.
- ^Wells A.F. (1984)Structural Inorganic Chemistry5th edition Oxford Science PublicationsISBN0-19-855370-6
- ^Magnetic susceptibility of the elements and inorganic compoundsArchived2012-01-12 at theWayback Machine
- ^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.
- ^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.
- ^Folmer, J.C.W.; Jellinek F.; Calis G.H.M (1988). "The electronic structure of pyrites, particularly CuS2and 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.
- ^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.
- ^Cotton, F. Albert;Wilkinson, Geoffrey;Murillo, Carlos A.; Bochmann, Manfred (1999),Advanced Inorganic Chemistry(6th ed.), New York: Wiley-Interscience,ISBN0-471-19957-5
- ^abLiang, W.; Whangbo M, -H (February 1993). "Conductivity anisotropy and structural phase transition in Covellite CuS".Solid State Communications.85(5): 405–408.Bibcode:1993SSCom..85..405L.doi:10.1016/0038-1098(93)90689-K.
- ^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.
- ^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.PMID11871554.