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Crystal structure of adamite at high temperature

Published online by Cambridge University Press:  02 January 2018

M. Zema*
Affiliation:
Dipartimento di Scienze della Terra e dell’Ambiente, Università degli Studi di Pavia, via Ferrata 9, I-27100 Pavia, Italy CNR-IGG, Sezione di Pavia, via Ferrata 9, I-27100 Pavia, Italy
S. C. Tarantino
Affiliation:
Dipartimento di Scienze della Terra e dell’Ambiente, Università degli Studi di Pavia, via Ferrata 9, I-27100 Pavia, Italy CNR-IGG, Sezione di Pavia, via Ferrata 9, I-27100 Pavia, Italy
M. Boiocchi
Affiliation:
Centro Grandi Strumenti, Università di Pavia, via Bassi 21, I-27100 Pavia, Italy
A. M. Callegari
Affiliation:
Dipartimento di Scienze della Terra e dell’Ambiente, Università degli Studi di Pavia, via Ferrata 9, I-27100 Pavia, Italy

Abstract

Structural modifications with temperature of adamite, Zn2(AsO4)(OH), were determined by single-crystal X-ray diffraction up to dehydration and collapse of the crystal structure. In the temperature range 25–400°C, adamite shows positive and linear expansion. Axial thermal expansion coefficients, determined over this temperature range, are αa = 1.06(2) × 10–5 K–1, αb = 1.99(2) × 10–5 K–1, αc = 3.7(1) × 10–6 K–1 and αV = 3.43(3) × 10–5 K–1. Axial expansion is then strongly anisotropic with αabc = 2.86: 5.38 : 1. Structure refinements of X-ray diffraction data collected at different temperatures allowed us to characterize the mechanisms by which the adamite structure accommodates variations in temperature. Expansion is limited mainly by edge sharing Zn(2) dimers along a and by edge sharing Zn(1) octahedra chains along c; on the other hand, connections of polyhedra along b, the direction of maximum expansion, is governed by corner sharing. Increasing temperature induces mainly an axial expansion of Zn(1) octahedron, which becomes more elongated, and no significant variations of the Zn(2) trigonal bipyramids and As tetrahedra. Starting from 400°C, deviation from a linear evolution of unit-cell parameters is observed, associated with some deterioration of the crystal, a sign of incipient dehydration. The process leads to the formation of Zn4(AsO4)2O.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2016

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References

Blessing, R.H. (1995) An empirical correction for absorption anisotropy. Acta Crystallographica A, 51, 3338.CrossRefGoogle ScholarPubMed
Blessing, R.H., Coppens, P. and Becker, P. (1974) Computer analysis of step-scanned X-ray data. Journal of Applied Crystallography, 7, 488–92.CrossRefGoogle Scholar
Gaines, R.V., Skinner, H.C.W.., Foord, E.E., Mason, B. and Rosenzweig, A. (1997) Dana's New Mineralogy. The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana. 8th Edition. John Wiley and Sons, Inc., New York.Google Scholar
Hawthorne, F.C. (1976) A refinement of the crystal structure of adamite.The Canadian Mineralogist, 14, 143148.Google Scholar
Hazen, R.M., Downs, R.T. and Prewitt, C.T. (2000) Principles of comparative crystal chemistry. Pp. 133 in: High-Temperature and High Pressure Crystal Chemistry (R.M. Hazen and R.T. Downs, editors). Reviews in Mineralogy and Geochemistry, 41. Mineralogical Society of America, Washington, DC CrossRefGoogle Scholar
Hill, R.J. (1976) The crystals structure and infrared properties of adamite.American Mineralogist, 61, 979986.Google Scholar
Ibers, J.A. and Hamilton, W.C. (1974) International Tables for X-ray Crystallography. Kynoch Press, Birmingham, UK.Google Scholar
Kato, T. and Y, Miura (1977) The crystal structures of adamite and paradamite. Mineralogical Journal, 8, 320328.CrossRefGoogle Scholar
Kokkoros, P. (1937) Über die Struktur von Adamin. Zeitschrift für Kristallographie, 96, 417–34.Google Scholar
Lehman, M.S. and Larsen, F.K. (1974) A method for location of the peaks in step-scan measured Bragg reflections. Acta Crystallographica A, 30, 580584.CrossRefGoogle Scholar
Makreski, P. Jovanovski, S. Pejov, L. Kloess, G. Hoebler, H.J. and Jovanovski, G. (2013) Theoretical and experimental study of the vibrational spectra of sarkinite Mn2(AsO4)(OH) and adamite Zn2(AsO4) (OH). Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 113, 3742.CrossRefGoogle Scholar
Mills, S.J., Kampf, A.R., Poirier, G., Raudsepp, M. and Steele, I.M. (2010) Auriacusite, Fe3+Cu2+AsO4O, the first M + member of the olivenite group, from the Black Pine mine, Montana, USA. Mineralogy and Petrology , 99, 113-120.CrossRefGoogle Scholar
North, A.C.T.., Phillips, D.C. and Mathews, F.S. (1968) A semi-empirical method of absorption correction. Acta Crystallographica , A24, 351-359.CrossRefGoogle Scholar
Schneider, H. and Eberhard, E. (1990) Thermal expansion of mullite. Journal of the American Ceramic Society , 73, 2073-2076.CrossRefGoogle Scholar
Sheldrick, G.M. (1998) SHELX97 – Programs for Crystal Structure Analysis (Release 97–2. Institut für Anorganische Chemie der Universität, Göttingen, Germany.Google Scholar
Sheldrick, G.M. (2003) SADABS . University of Göttingen, Germany.Google Scholar
Toman, K. (1978) Ordering in olivenite–adamite solid solutions. Acta Crystallographica , 34, 715-721.CrossRefGoogle Scholar
Xu, J., Ma, M., Wei, S., Hu, X., Liu, Y., Liu, J., Fan, D. and Xie, H. (2014) Equation of state of adamite up to 11 GPa: a synchrotron X-ray diffraction study. Physics and Chemistry of Minerals , 41, 547-554.CrossRefGoogle Scholar
Zema, M., Tarantino, S.C. and Callegari, A.M. (2010) Thermal behaviour of libethenite from room temperature up to dehydration. Mineralogical Magazine , 74, 553-565.CrossRefGoogle Scholar
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