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X-ray powder diffraction analysis of two new magnesium selenate hydrates, MgSeO4·9H2O and MgSeO4·11H2O

Published online by Cambridge University Press:  08 May 2015

A. Dominic Fortes*
Affiliation:
Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK Department of Earth and Planetary Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected]

Abstract

Several hitherto unknown hydrates of magnesium selenate have been formed by quenching aqueous solutions of MgSeO4 in liquid nitrogen. MgSeO4·11H2O is apparently isostructural with the mineral meridianiite (MgSO4·11H2O), being triclinic, $P{\rm \bar 1}$, Z = 2, with unit-cell parameters a = 6.779 00(8) Å, b = 6.965 16(9) Å, c = 17.4934(2) Å, α = 87.713(1)°, β = 89.222(1)°, γ = 63.121(1)°, and V = 736.15(1) Å3 at −25 °C. MgSeO4·9H2O represents a new hydration state in the MgSeO4–H2O system; it is monoclinic, space-group P21/c, Z = 4, with unit-cell parameters a = 7.270 24(6) Å, b = 10.510 94(9) Å, c = 17.4030(2) Å, β = 109.447(1)°, and V = 1254.02(1) Å3 at −22 °C. The heavy-atom structure of MgSeO4·9H2O has been determined by direct-space methods from X-ray powder diffraction data and consists of isolated Mg(H2O)62+ octahedra and SeO42− tetrahedra linked by hydrogen bonds. The remaining three water molecules occupy the space between the polyhedral ions, contributing to the H-bonded network, which comprises 4-, 5-, and 6-membered rings. A third phase has been observed to crystallise prior to the 11-hydrate upon warming of liquid-nitrogen-quenched glass, but this transforms rapidly to the meridianiite-structured 11-hydrate and the identity of this phase is unclear.

Type
Technical Articles
Copyright
Copyright © International Centre for Diffraction Data 2015 

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References

Baur, W. H. (1964). “On the crystal chemistry of salt hydrates. IV. The refinement of the crystal structure of MgSO4·7H2O (epsomite),” Acta Crystallogr. 17, 13611369.Google Scholar
Boultif, A. and Louër, D. (2004). “Powder pattern indexing with the dichotomy method,” J. Appl. Cryst. 37, 724731.Google Scholar
Brand, H. E. A., Fortes, A. D., Wood, I. G., Knight, K. S., and Vočadlo, L. (2009). “The thermal expansion and crystal structure of mirabilite (Na2SO4·10D2O) from 4.2–300 K, determined by time-of-flight neutron powder diffraction,” Phys. Chem. Min. 36, 2946.Google Scholar
De Wolff, P. M. (1968). “A simplified criterion for the reliability of a powder pattern indexing,” J. Appl. Cryst. 5, 108113.Google Scholar
Favre-Nicolin, V. and Černý, R. (2002). “FOX, ‘free objects for crystallography’: a modular approach to ab initio structure determination from powder diffraction,” J. Appl. Cryst. 35, 734743.Google Scholar
Favre-Nicolin, V. and Černý, R. (2004). “A better FOX: using flexible modeling and maximum likelihood to improve direct-space ab initio structure determination from powder diffraction,” Z. Krist. 219, 847856.Google Scholar
Ferraris, G., Jones, D. W., and Yerkess, J. (1973). “Refinement of the crystal structure of magnesium sulphate heptahydrate (epsomite) by neutron diffraction,” J. Chem. Soc. Dalton Trans. 1973, 816821.Google Scholar
Fortes, A. D. (2014). Analogue materials for high-pressure studies of planetary ices, in British Crystallographic Society Spring Meeting, Loughborough, April 8th 2014.Google Scholar
Fortes, A. D. and Gutmann, M. J. (2014). “Crystal structure of magnesium selenate heptahydrate, MgSeO4·7H2O, from neutron time-of-flight data,” Acta Crystallogr. Sect. E. 70, 134137.Google Scholar
Fortes, A. D. and Wood, I. G. (2012). “X-ray powder diffraction analysis of a new magnesium chromate hydrate, MgCrO4·11H2O,” Powder Diffr. 27, 811.Google Scholar
Fortes, A. D., Wood, I. G., Grigoriev, D., Alfredsson, M., Kipfstuhl, S., Knight, K. S., and Smith, R. I. (2004). “No evidence of large-scale proton ordering in Antarctic ice from powder neutron diffraction,” J. Chem. Phys. 120, 1137611379.Google Scholar
Fortes, A. D., Wood, I. G., and Knight, K. S. (2008). “The crystal structure and thermal expansion tensor of MgSO4·11D2O (meridianiite) determined by neutron powder diffraction,” Phys. Chem. Min. 35, 207221.Google Scholar
Fortes, A. D., Wood, I. G., and Tucker, M. G. (2009). The effect of pressure on the structure of meridianiite (MgSO 4 ·11D 2 O). ISIS Experimental Report, RB910226, Rutherford Appleton Laboratory, Oxford, UK.Google Scholar
Fortes, A. D., Browning, F., and Wood, I. G. (2012a). “Cation substitution in synthetic meridianiite (MgSO4·11H2O) I: X-ray powder diffraction analysis of quenched polycrystalline aggregates,” Phys. Chem. Min. 39, 419441.Google Scholar
Fortes, A. D., Browning, F., and Wood, I. G. (2012b). “Cation substitution in synthetic meridianiite (MgSO4·11H2O) II: variation in unit-cell parameters determined from X-ray powder diffraction data,” Phys. Chem. Min. 39, 443454.Google Scholar
Fortes, A. D., Wood, I. G., and Fernandez-Alonso, F. (2012c). Thermoelastic properties and high-pressure decomposition of MgSO 4 ·11D 2 O. ISIS Experimental Report, RB1110039, Rutherford Appleton Laboratory, Oxford, UK.Google Scholar
Fortes, A. D., Wood, I. G., and Gutmann, M. J. (2013). “MgSO4·11H2O and MgCrO4·11H2O from time-of-flight neutron single-crystal Laue data,” Acta Crystallogr. Sect. C 69, 324329.CrossRefGoogle ScholarPubMed
Genceli, F. E., Shinochirou, H., Yoshinori, I., Toshimitsu, S., Hondoh, T., Kawamura, T., and Witkamp, G.-J. (2009). “Meridianiite detected in ice,” J. Glaciol. 55, 117122.Google Scholar
Kamburov, S., Schmidt, H., Voigt, W., and Balarew, C. (2014). “Similarities and peculiarities between the crystal structures of the hydrates of sodium sulfate and selenate,” Acta Crystallogr. Sect. B 70, 714722.Google Scholar
Kargel, J. S. (1991). “Brine volcanism and the interior structures of asteroids and icy satellites,” Icarus 94, 368390.Google Scholar
Klein, A. (1940). “Étude sur les séléniates des métaux de la série magnésienne,” Ann. Chim. 14, 263317.Google Scholar
Kolitsch, U. (2001). “Copper(II) selenate pentahydrate, CuSeO4·5H2O,” Acta Crystallogr. Sect. E 57, i104i105.Google Scholar
Kolitsch, U. (2002). “Magnesium selenate hexahydrate, MgSeO4·6H2O,” Acta Crystallogr., Sect. E 58, i3i5.Google Scholar
Krivovichev, S. V. (2007). “Crystal chemistry of selenates with mineral-like structures. III. Heteropolyhedral chains in the crystal structure of [Mg(H2O)4(SeO4)]2(H2O),” Geol. Ore Dep. 49(7), 537541.Google Scholar
Larson, A. C. and Von Dreele, R. B. (2000). General Structure Analysis System (GSAS). Los Alamos National Laboratory Report, LAUR 86-748.Google Scholar
Meyer, J. and Aulich, W. (1928). “Zur kenntnis der doppelsalze der selensäure,” Z. Anorg. Allg. Chem. 172, 321343.Google Scholar
Peterson, R. C. and Wang, R. (2006). “Crystal molds on Mars: melting of a possible new mineral species to create Martian chaotic terrain,” Geology 34, 957960.Google Scholar
Peterson, R. C., Nelson, W., Madu, B., and Shurvell, H. F. (2007). “Meridianiite: a new mineral species observed on Earth and predicted to exist on Mars,” Am. Min. 92, 17561759.Google Scholar
Putz, H. and Brandenburg, K. (2006). Diamond – Crystal and Molecular Structure Visualization (Crystal Impact – GbR, Bonn, Germany) http://www.crystalimpact.com/diamond.Google Scholar
Röttger, K., Endriss, A., Ihringer, J., Doyle, S., and Kuhs, W. F. (1994). “Lattice constants and thermal expansion of H2O and D2O ice Ih between 10 and 265 K,” Acta Crystallogr., Sect. B 50, 644648.CrossRefGoogle Scholar
Smith, G. S. and Snyder, R. L. (1979). “ F N : a criterion for rating powder diffraction patterns and evaluating the reliability of powder-pattern indexing,” J. Appl. Cryst. 12, 6065.Google Scholar
Snyman, H. C., and Pistorius, C. W. F. T. (1964). “Crystallographic data for NiSeO4 6H2O and MgSeO4 6H2O,” Z. Kristallogr. 119, 465467.CrossRefGoogle Scholar
Stoilova, D. and Koleva, V. (1995). “X-ray diffraction study on MgSeO4·6H2O at elevated temperatures,” Cryst. Res. Tech. 30, 547551.CrossRefGoogle Scholar
Toby, B. H. (2001). “ EXPGUI, a graphical user interface for GSAS ,” J. Appl. Cryst. 34, 210213.CrossRefGoogle Scholar
Toby, B. H. (2003). “CIF applications. XII. Inspecting Rietveld fits from pdCIF: pdCIFplot ,” J. Appl. Cryst. 36, 12851287.Google Scholar
Weil, M. and Bonneau, B. (2014). “Crystal structures of Na2SeO4·1.5H2O and Na2SeO4·10H2O,” Acta Cryst. Sect. E 70, 5457.Google Scholar
Wood, I. G., Hughes, N., Browning, F., and Fortes, A. D. (2012). “A compact transportable, thermoelectrically-cooled cold stage for reflection geometry X-ray powder diffraction,” J. Appl. Crystallogr. 45, 608610.Google Scholar
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