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The crystal structure and compositional range of mckinstryite

Published online by Cambridge University Press:  05 July 2018

U. Kolitsch*
Affiliation:
Mineralogisch-Petrographische Abt., Naturhistorisches Museum, Burgring 7, A-1010 Wien, Austria

Abstract

The previously unknown crystal structure of mckinstryite, originally described as Ag1.18Cu0.82S or (Ag,Cu)2S, was solved and refined using single-crystal X-ray diffractometer data collected from a sample from the Clara mine, Black Forest (Mo-Kα radiation, CCD area detector, R1(F) = 3.85%). Mckinstryite has the refined formula Ag4.92Cu3.08S4 or Ag1.23Cu0.77S (idealized Ag5Cu3S4 or Ag1.25Cu0.75S) and crystallizes in space group Pnma (no. 62), with a = 14.047(3) Å, b = 7.805(2) Å , c = 15.691(3) Å, V = 1720.3(7) Å3, Z = 8. The structure contains five Ag, six Cu and eight S sites in the asymmetric unit. One of the Ag sites shows minor Cu-for-Ag substitution. The topology is based on flat, interrupted (010) layers of Cu and S atoms (all atoms on y = 0.25), in which the Cu atoms show triangular or two-coordination to S (interrupted {6,3} tiling). These layers alternate with uneven layers consisting of Ag atoms showing irregular three- to two-coordination to S. Some fairly short Ag–Cu contact distances (2.781–2.884 Å) strongly indicate that metal-metal interaction plays an important role in mckinstryite. The topology is related to that of stromeyerite (∼AgCuS) which contains complete flat layers of Cu atoms triangularly coordinated to S atoms, alternating with layers of loosely packed Ag atoms.

A critical evaluation of literature data on the chemical composition and unit-cell parameters of mckinstryite confirms the presence of a small compositional range of mckinstryite which extends approximately from Ag1.18Cu0.82S to Ag1.25Cu0.75S, with the presently studied sample being fairly Agrich. The accurate limits of this range at ambient temperature are still to be determined.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2010

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References

Asadov, Yu.G., Alyev, Yu.I. and Jafarov, K.M. (2008) X-ray diffraction study of compounds in the Ag2S-Cu2S system. Inorganic Materials, 44, 460466.CrossRefGoogle Scholar
Atanasov, V. and Lavrentiev, Yu. (1973) New occurrence of mackinstryite. Spisanie na Bulgarskoto Geologichesko Druzhestvo, 34, 309320. (in Bulgarian).Google Scholar
Baker, C.L., Lincoln, F.J. and Johnson, A.W.S. (1991) A low-temperature structural phase transformation in CuAgS. Acta Crystallographica B, 47, 891899.CrossRefGoogle Scholar
Baker, C.L., Lincoln, F.J. and Johnson, A.W.S. (1992) Crystal structure determination of Ag3CuS2 from powder X-ray diffraction data. Australian Journal of Chemistry, 45, 14411449.CrossRefGoogle Scholar
Bergstöl, S. and Vokes, F.M. (1974) Stromeyerite and mackinstryite from the Godejord polymetallic sulfide deposit, central Norwegian Caledonides. Mineralium Deposita, 9, 325337.CrossRefGoogle Scholar
Bindi, L. and Pratesi, G. (2005) Selenojalpaite, Ag3CuSe2, a new mineral species from the SkrikerumCu-Ag-Tl selenide ore deposit, Småland, southeastern Sweden. The Canadian Mineralogist, 43, 13731377.CrossRefGoogle Scholar
Borchert, W. and Patzak, I. (1955) Solid-state reactions of copper and silver with selenium. Heidelberger Beiträge zur Mineralogie und Petrographie, 4, 434442.Google Scholar
Brown, I.D. (1996) VALENCE: a programfor calculating bond valences. Journal of Applied Crystallography, 29, 479480.CrossRefGoogle Scholar
Brown, I.D. and Altermatt, D. (1985) Bond-valence parameters obtained from a systematic analysis of the inorganic crystal structure database. Acta Crystallographica B, 41, 244247.CrossRefGoogle Scholar
Djurle, S. (1958) X-ray study of the Ag-Cu-S system. Acta Chemica Scandinavica, 12, 14271436.CrossRefGoogle Scholar
Fischer, R.X. and Tillmanns, E. (1988) The equivalent isotropic displacement factor. Acta Crystallographica C, 44, 775776.CrossRefGoogle Scholar
Frueh, A.J. Jr. (1955) The crystal structure of stromeyerite, AgCuS: a possible defect structure Zeitschrift für Kristallographie, 106, 299307.Google Scholar
Frueh, A.J. Jr., Czamanske, G.K. and Knight, C. (1957) The crystallography of eucairite, CuAgSe. Zeitschrift für Kristallographie, 108, 389396.CrossRefGoogle Scholar
Gelato, L.M. and Parthé, E. (1987) STRUCTURE TIDY – a computer program to standardize crystal structure data. Journal of Applied Crystallography, 20, 139143.CrossRefGoogle Scholar
Kubaschewski, O., Lebrun, N., Geupel, S., Fenstad, J. and Perrot, P. (2006) Silver-Copper-Sulfur. Landolt- Börnstein - Group IV Physical Chemistry, Non- Ferrous Metal Systems. Part 1, Vol. 11C1, 3042.Google Scholar
Otwinowski, Z., Borek, D., Majewski, W. and Minor, W. (2003) Multiparametric scaling of diffraction intensities. Acta Crystallographica A, 59, 228234.CrossRefGoogle ScholarPubMed
Pekov, I.V. and Karpenko, V.Yu. (1996) Unusual stromeyerite-mckinstryite pseudomorphs after dyscrasite in the Sarbai deposit of northern Kazakhstan. Vestnik Moskovskogo Universiteta, Seriya 4: Geologiya, (6), 4550. (in Russian).Google Scholar
Robinson, B.W. and Morton, R.D. (1971) Mckinstryite fromthe Echo Bay Mine N.W.T., Canada. Economic Geology, 66, 342347.CrossRefGoogle Scholar
Rojkovič, I. (1973) Silver mineralization at Great Bear Lake, Canada. Geologicky Zbornik — Geologica Carpathica, 24, 325338.Google Scholar
Schäfer, E. (1995) Experimental investigations in the Cu-Ag-S-Se system. Neues Jahrbuch für Mineralogie Abhandlungen, 169, 301304.Google Scholar
Schmidt, J.A. and Sagua, A.E. (1999) The chemical diffusion coefficient of silver in Ag1.2Cu0.8S (β-phase) determined by the potentiometric method. Anales de la Asociacion Quimica Argentina, 87, 111120.Google Scholar
Shape Software (1999) ATOMS for Windows and Macintosh V6.3. Kingsport, TN 37663, U.S.A. Google Scholar
Sheldrick, G.M. (2008) A short history of SHELX . Acta Crystallographica A, 64, 112122.CrossRefGoogle Scholar
Skinner, B.J. (1966) The system Cu-Ag-S. Economic Geology, 61, 126.CrossRefGoogle Scholar
Skinner, B.J., Jambor, J.L. and Ross, M. (1966) Mckinstryite, a new copper-silver sulfide. Economic Geology, 61, 13831389.CrossRefGoogle Scholar
Skomorokhov, A.N., Trots, D.M., Sashin, I.L., Fuess, H., Jadrowskii, E.L. and Ovchinnikov, S.G. (2008) Phonon density of states in γ-, β-, and α-AgCuS. Physics of the Solid State, 50, 318322.CrossRefGoogle Scholar
Suhr, N. (1955) The Ag2S-Cu2S system. Economic Geology, 50, 347350.CrossRefGoogle Scholar
Šulcová, V. and Kašpar, P. (1986) Mckinstryite and jalpaite fromthe Pošepny vein at Vrančice near Příbram, Czechoslovakia. Časopis pro Mineralogii a Geologii, 31, 183184. (in Czech).Google Scholar
Tokuhara, Y., Tezuka, K., Shan, Y.J. and Imoto, H. (2009) Syntheses of complex sulfides AgCuS and Ag3CuS2 from the elements under hydrothermal conditions. Journal of the Ceramic Society of Japan, 117, 359362. (in Japanese).CrossRefGoogle Scholar
Trots, D.M., Senyshyn, A., Mikhailova, D.A., Knapp, M.,Bähtz, C., Hölzel, M. and Fuess, H. (2007) High-temperature thermal expansion and structural behaviour of stromeyerite, AgCuS. Journal of Physics: Condensed Matter, 19, 136204/1-136204/13.Google Scholar
Trots, D.M., Senyshyn, A., Mikhailova, D.A., Vad, T. and Fuess, H. (2008) Phase transitions in jalpaite, Ag3CuS2 . Journal of Physics: Condensed Matter, 20, 455204/1-455204/10.Google Scholar
Yarenskaya, M.A., Kostogonov, V.G., Muratov, E.M. and Slyusarev, A.P. (1975) First find of mackinstryite in the USSR. Zapiski Vsesoyuznogo Mineralogicheskogo Obshchestva, 104, 6265. (in Russian).Google Scholar
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