Abstract
We present the first equation of state and structure refinements at high pressure of single-crystal phase egg, AlSiO3OH. Phase egg is a member of the Al2O3-SiO2-H2O system, which contains phases that may be stable along a typical mantle geotherm (Fukuyama et al. 2017) and are good candidates for water transport into Earth’s deep mantle. Single-crystal synchrotron X‑ray diffraction was performed up to 23 GPa. We observe the b axis to be the most compressible direction and the b angle to decrease up to 16 GPa and then to remain constant at a value of ~97.8° up to the maximum experimental pressure reached. Structure refinements performed at low pressures reveal a distorted octahedron around the silicon atom due to one of the six Si-O bond lengths being significantly larger than the other five. The length of this specific Si-O4 bond rapidly decreases with increasing pressure leading to a more regular octahedron at pressures above 16 GPa. We identified the shortening of the Si-O4 bond and the contraction of the vacant space between octahedral units where the hydrogen atoms are assumed to lie as the major components of the compression mechanism of AlSiO3OH phase egg.
Acknowledgments
This research was supported through the project “GeoMaX” funded under the Emmy-Noether Program of the German Science Foundation (MA4534/3-1).
References cited
Angel, R.J. (2000) Equation of State. Reviews in Mineralogy and Geochemistry, 41, 35–59.10.2138/rmg.2000.41.2Search in Google Scholar
Angel, R.J., and Finger, L.W. (2011) SINGLE: a program to control single-crystal diffractometers. Journal of Applied Crystallography, 44, 247–251.10.1107/S0021889810042305Search in Google Scholar
Angel, R.J., Alvaro, M., and Gonzales-Platas, J. (2014) EosFit7c and a Fortran module (library) for equation of state calculations. Zeitschrift für Kristallographie, 229, 405–419.10.1515/zkri-2013-1711Search in Google Scholar
Deweale, A., Torrent, M., Loubeyre, P., and Mezouar, M. (2008) Compression curves of transition metals in the Mbar range: Experiments and projector augmented-wave calculations. Physical Review B, 78, 104102.10.1103/PhysRevB.78.104102Search in Google Scholar
Eggleton, R.A., Boland, J.N., and Ringwood, A.E. (1978) High pressure synthesis of a new aluminium silicate: Al5Si5O17(OH). Geochemical Journal, 12, 191–194.10.2343/geochemj.12.191Search in Google Scholar
Farrugia, L.J. (2012) WinGX and ORTEP for Windows: an update. Journal of Applied Crystallography, 45, 849–854.10.1107/S0021889812029111Search in Google Scholar
Friedrich, A., Wilson, D.J., Haussühl, E., Winkler, B., Morgenroth, W., Refson, K., and Milman, V. (2007) High-pressure properties of diaspore, AlO(OH). Physics and Chemistry of Minerals, 34, 145–157.10.1007/s00269-006-0135-5Search in Google Scholar
Fukuyama, K., Ohtani, E., Shibazaki, Y., Kagi, H., and Suzuki, A. (2017) Stability field of phase egg, AlSiO3OH at high pressure and high temperature: possible water reservoir in mantle transition zone. Journal of Mineralogical and Petrological Sciences, 112, 31–35.10.2465/jmps.160719eSearch in Google Scholar
Gatta, G.D., Morgenroth, W., Dera, P., Petitgirard, S., and Liermann, H.-P. (2014) Elastic behavior and pressure-induced structure evolution of topaz up to 45 GPa. Physics and Chemistry of Minerals, 41, 569–577.10.1007/s00269-014-0670-4Search in Google Scholar
Hazen, R.M., Downs, R.T., and Prewitt, C.T. (2000) Principle of comparative crystal chemistry. Reviews in Mineralogy and Geochemistry, 41, 1–33.10.1515/9781501508707-005Search in Google Scholar
Ibers, J.A., and Hamilton, W.C. (1974) International Tables for X‑ray Crystallography, vol. IV. Kynoch, Birmingham, U.K.Search in Google Scholar
Kantor, I., Prakapenka, V., Kantor, A., Dera, P., Kurnosov, A., Sinogeikin, S., Dubrovinskaia, N., and Dubrovinsky, L. (2012) BX90: A new diamond anvil cell design for X‑ray diffraction and optical measurements. Review of Scientific Instruments, 83, 125102.10.1063/1.4768541Search in Google Scholar PubMed
King, H.E., and Finger, L.W. (1979) Diffracted beam crystal centering and its application to high-pressure crystallography. Journal of Applied Crystallography, 12, 374–378.10.1107/S0021889879012723Search in Google Scholar
Kurnosov, A., Kantor, I., Boffa-Ballaran, T., Lindhardt, S., Dubrovinsky, L., Kuznetsov, A., and Zehnder, B.H. (2008) A novel gas-loading system for mechanically closing of various types of diamond anvil cells. Review of Scientific Instruments, 79, 045110.10.1063/1.2902506Search in Google Scholar PubMed
Nye, J.F. (1985) Physical Properties of Crystals: Their Representation by Tensors and Matrices, 352 p. Oxford University Press.Search in Google Scholar
Ohashi, Y., and Burnham, C.W. (1973) Clinopyroxene lattice deformations: The role of chemical substitution and temperature. American Mineralogist, 58, 843–849.Search in Google Scholar
Pamato, M.G., Myhill, R., Boffa Ballaran, T., Frost, D.J., Heidelbach, F., and Miyajima, N. (2015) Lower-mantle water reservoir implied by the extreme stability of a hydrous aluminosilicate. Nature Geoscience, 8, 75–79.10.1038/ngeo2306Search in Google Scholar
Sano, A., Ohtani, E., Kubo, T., and Funakoshi, K. (2004) In situ X‑ray observation of decomposition of hydrous aluminum silicate AlSiO3OH and aluminum oxide hydroxide d-AlOOH at high pressure and temperature. Journal of Physics and Chemistry of Solids, 65, 1547–1554.10.1016/j.jpcs.2003.12.015Search in Google Scholar
Schmidt, M.W., Finger, L.W., Angel, R.J., and Dinnebier, R.E. (1998) Synthesis, crystal structure, and phase relations of AlSiO3OH, a high-pressure hydrous phase. American Mineralogist, 83, 881–888.10.2138/am-1998-7-820Search in Google Scholar
Sheldrick, G.M. (2008) A short history of SHELX. Acta Crystallographica, A64, 112–122.10.1107/S0108767307043930Search in Google Scholar PubMed
Tsuchiya, J., Tsuchiya, T., Tsuneyuki, S., and Yamanaka, T. (2002) First principles calculation of a high-pressure hydrous phase, d-AlOOH. Geophysical Research Letters, 29. 190910.1029/2002GL015417Search in Google Scholar
Vanpeteghem, C.B., Ohtani, E., Kondo, T., Takemura, K., and Kikegawa, T. (2003) Compressibility of phase Egg AlSiO3OH: Equation of state and role of water at high pressure. American Mineralogist, 88, 1408–1411.10.2138/am-2003-1002Search in Google Scholar
Wirth, R., Vollmer, C., Brenker, F., Matsyuk, S., and Kaminsky, F. (2007) Inclusions of nanocrystalline hydrous aluminium silicate “phase egg” in superdeep diamonds from Juina (Mato Grosso State, Brazil). Earth and Planetary Science Letters, 259, 384–399.10.1016/j.epsl.2007.04.041Search in Google Scholar
Xu, W., Greenberg, E., Rozenberg, G.K., Pasternak, M.P., Bykova, E., Boffa Ballaran, T., Dubrovinsky, L., Prakapenka, V., Hanfland, M., Vekilova, O.Y., Simak, S.I., and Abrikosov, I.A. (2013) Pressure-induced hydrogen bond symmetrization in iron oxyhydroxide. Physical Review Letters, 111, 175501.10.1103/PhysRevLett.111.175501Search in Google Scholar PubMed
Xue, X., Kanzaki, M., Fukui, H., Ito, E., and Hashimoto, T. (2006) Cation order and hydrogen bonding of high-pressure phases in the Al2O3-SiO2-H2O system: An NMR and Raman study. American Mineralogist, 91, 850–861.10.2138/am.2006.2064Search in Google Scholar
© 2018 Walter de Gruyter GmbH, Berlin/Boston
