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Low-temperature crystal structure evolution of (Na,Ca)(Cr,Mg)Si2O6 pyroxene

Published online by Cambridge University Press:  05 July 2018

F. Nestola*
Affiliation:
Dipartimento di Geoscienze, Università di Padova, Via Giotto 1, 35010, Padova, Italy
A. Madsen
Affiliation:
Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark
M. Tribaudino
Affiliation:
Dipartimento di Scienze della Terra, Università di Parma, Parco Area delle Scienze 157/A, 43100, Parma, Italy
T. Balić-Žunić
Affiliation:
Department of Geography and Geology, University of Copenhagen, Øster Voldgade 10, 1350 Copenhagen, Denmark
H. Ohashi
Affiliation:
Hashi Institute for Silicate Science, Nishinakanobu 1-9-25, Shinagawa, Tokyo 142-0054, Japan
L. Secco
Affiliation:
Dipartimento di Geoscienze, Università di Padova, Via Giotto 1, 35010, Padova, Italy
A. Dal Negro
Affiliation:
Dipartimento di Geoscienze, Università di Padova, Via Giotto 1, 35010, Padova, Italy

Abstract

The crystal structure of a clinopyroxene with composition (Na0.75Ca0.25)(Cr0.75Mg0.25)Si2O6 was refined at 100, 150, 200, 250 and 298 K. The work was performed in the context of an investigation on the low-temperature behaviour of A+M3+Si2O6 (with A dominant in Na and M = transition elements) pyroxenes in order to provide new insights concerning the phase transition and anomalies recently found in the low-temperature behaviour of NaTiSi2O6 and NaGaSi2O6 compounds. The refinements were done in the C2/c space group (wR2 between 0.048 and 0.068), and no change of symmetry was observed down to 100 K. Highly-anisotropic axial thermal expansion occurs with the scheme αb ≥ αb > αc.

The M2, M1 and T polyhedra expand with αM2 > αM1 αT as generally observed in pyroxenes. A discontinuity in the M1 polyhedral volume is observed between 200 and 250 K, similar to the one observed in NaGaSi2O6 between 190 and 235 K.

The atomic displacement parameters are scaled according to the following pattern: UM2 > UO2 > UO3U01 > UTUM1 Comparison with previous data along the CaMgSi2O-NaCrSi2O6 join suggests significant positional disorder for the O1 oxygen, due to repulsion of the 2p orbitals of O1 and the non-bondine 3d electrons of Cr.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2008

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References

Balic-Zunic, T. (2007) Use of three-dimensional parameters in the analysis of crystal structures under compression. Pp. 157184 in: Pressure-Induced Phase Transitions (A. Grzechnik, editor). Transworld Research Network, Trivandrum, India.Google Scholar
Balic-Zunic, T. and Vickovic, I. (1996) IVTON - a program for the calculation of geometrical aspects of crystal structures and some crystal chemical applications. Journal of Applied Crystallography, 29, 305306.CrossRefGoogle Scholar
Cameron, M., Sueno, S., Prewitt, C.T. and Papike, JJ. (1973) High-temperature crystal-chemistry of ac-mite, diopside, hedenebrgite, jadeite, spodumente and ureyite. American Mineralogist, 58, 594618.Google Scholar
Duisenberg, AJ.M. (1998) Reflections on Area Detectors. PhD thesis, Utrecht.Google Scholar
Duisenberg, A.J.M., Hooft, R.W.W., Schreurs, A.M.M. and Kroon, J. (2000) Accurate cells from area-detector images. Journal of Applied Crystallography, 33, 893898.CrossRefGoogle Scholar
Isobe, M., Ninomiyai, E., Vasil'ev, A.N. and Ueda, Y. (2002) Novel phase transition in spin-1/2 linear chain systems: NaTiSi2O6 and LiTiSi2O6 . Journal of the Physical Society of Japan, 71, 14231426.CrossRefGoogle Scholar
Mackay, S., Gilmore, C.J., Edwards, C Tremayne, M., Stuart, N. and Shankland, K. (1998) MAXUS. A Computer Program for the Solution and Refinement of Crystal Structures from Diffraction Data. University of Glasgow, Scotland, UK, Nonius BV, Delft, The Netherlands and MacScience Co. Ltd., Yokohama, Japan.Google Scholar
Millet, P., Mila, F., Zhang, F.C., Mambrini, M., van Oosten, A.B., Pashchenko, V.A., Sulpice, A. and Stepanov, A. (1999) Biquadratic interactions and spin-Peierls transition in the spin-1 chain LiVGe2O6 . Physical Review Letters, 83, 41764179.CrossRefGoogle Scholar
Nestola, F., Rotiroti, N Bruno, M., Tribaudino, M., van Smaalen, S., Ohashi, H. and Redhammer, G. (2007a) Low-temperature behavior of NaGaSi2O6 . American Mineralagist, 92, 560569.CrossRefGoogle Scholar
Nestola, F., Tribaudino, M., Boffa Ballaran, T., Liebske, C. and Bruno, M. (20076) The crystal structure of pyroxenes along the jadeite-hedenbergite and ja-deite-aegirine joins. American Mineralogist, 92, 14921501.CrossRefGoogle Scholar
Nonius, B.V. (1999) COLLECT; data collection software. Nonius BV, The Netherlands.Google Scholar
Ohashi, H. (1977) Synthesis of kosmochlor-diopside solid solution. Journal of Japan Association of Mineralogical and Petrological Economic Geology, 72, 259262.CrossRefGoogle Scholar
Prencipe, M., Tribaudino, M., Pavese, A., Hoser, A. and Reehuis, M. (2000) Single-crystal neutron-diffraction investigation of diopside at 10 K. The Canadian Mineralogist, 38, 183189.CrossRefGoogle Scholar
Redhammer, G.J. and Roth, G. (2004) Structural changes upon the temperature dependent C2lc—P2\lc phase transition in LiMe3+Si2O6 clino-pyroxenes, Me = Cr, Ga, Fe, V, Sc and In. Zeitschrifi fur Kristallographie, 219, 585605.Google Scholar
Redhammer, G.J., Ohashi, H. and Roth, G. (2003) Single-crystal structure refinement of NaTiSi2O6clinopyroxene at low temperatures (298 < T < 100 K). Ada Crystallographica, A59, 730746.Google Scholar
Redhammer, G.J., Amthauer, G., Roth, G., Tippelt, G. and Lottermoser, W. (2006) Single-crystal X-ray diffraction and temperature dependent Fe57 Mossbauer spectroscopy on the hedenbergite-aegir-ine (Ca,Na)(Fe2+,Fe3+)Si2O6 solid solution. American Mineralogist, 91, 12711292.CrossRefGoogle Scholar
Sheldrick, G.M. (1997) SHELX-97. Institut fur Anorganische Chemie, University of Gottingen, Germany.Google Scholar
Tribaudino, M., Nestola, F. and Ohashi, H. (2005) High temperature single crystal investigation in a clinopyroxene of composition (Na0.5Ca0.5)(cr0.5mg0.5) Si2O6 . European Journal of Mineralogy, 17, 297304.CrossRefGoogle Scholar
Vasiliev, A.N., Ignatchik, O.L., Sokolov, A.N., Hiroi, Z., Isobe, M. and Ueda, Y. (2005) Long-range magnetic order in quasi-one-dimensional chromium-based, S=3/2 pyroxenes, (Li,Na)Cr(Si,Ge)2O6 . Physical Review, B72, 1241212415.CrossRefGoogle Scholar
Wilson, A.J.C. and Prince, E. (1999) International Tables for Crystallography. Kluwer Academic, Dordrecht, The Netherlands.Google Scholar