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Structures of the 2:1 Layers of Pyrophyllite and Talc

Published online by Cambridge University Press:  01 January 2024

Victor A. Drits ,
Stephen Guggenheim ,
Bella B. Zviagina  and
Toshihiro Kogure
Victor A. Drits
Affiliation:
Geological Institute of the Russian Academy of Science, Pyzhevsky per. 7, 119017 Moscow, Russia
Stephen Guggenheim
Affiliation:
Department of Earth and Environmental Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
Bella B. Zviagina*
Affiliation:
Geological Institute of the Russian Academy of Science, Pyzhevsky per. 7, 119017 Moscow, Russia
Toshihiro Kogure
Affiliation:
Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
*
*E-mail address of corresponding author: [email protected]
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Abstract

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To determine the relationships between the symmetry of the overall pyrophyllite and talc structure and the symmetry of individual layers, the geometry and symmetry of each 2:1 layer of pyrophyllite and talc were analyzed. For each, the previously published, refined unit cell may be rotated clockwise by ~60° for comparison to a layer unit cell. In pyrophyllite, the layer unit cell is ideal and shown to be orthogonal with C2/m symmetry. The agreement between the refined atomic coordinates and those calculated for the layer with C2/m symmetry confirms that the symmetry of the pyrophyllite layer is C2/m. The obliquity of the pyrophyllite refined cell results from the layer stacking and the choice of unit cell, but the interlayer stacking sequence does not disturb the layer symmetry. In contrast, talc has an oblique layer cell, without a mirror plane. For the most part, the distortion of the talc 2:1 layer is probably caused by an elongation of unshared O-O lateral edges around M1 that creates a slight corrugation of the octahedral sheet surface. Perhaps of lesser importance, the distortion of the talc layer cell may result from Coulombic interactions between cations of adjacent layers, and these cation-to-cation distances are sufficiently large (~6–7.5 Å) that the weak van der Waals forces that stabilize the stacking are not overcome. Because pyrophyllite has a vacant octahedral site, similar interactions are not present, and this results in a more idealized layer symmetry.

Phyllosilicates consisting of layers with an orthogonal cell and mirror plane (pyrophyllite, kaolinite, sudoite) were shown to have similar stacking faults. In these structures, the 2:1 or 1:1 layers have uniform orientation, and stacking faults occur owing to interstratifications of two alternative interlayer displacements in the same crystal that are related by a mirror plane in the projection on the (001) plane. In talc, stacking faults are associated with layer rotations by ±120°, whereas the lateral displacement between the adjacent tetrahedral sheets across the interlayer region is relatively ordered.

Keywords

SymmetryNature of Stacking FaultsPyrophylliteTalcUnit-cell Parameters
Type
Article
Information
Clays and Clay Minerals , Volume 60 , Issue 6 , December 2012 , pp. 574 - 587
Copyright
Copyright © Clay Minerals Society 2012

References

Bookin, A.S. Drits, V.A. Plançon, A. and Tchoubar, C., 1989 Stacking faults in kaolin-group minerals in the light of real structural features Clays and Clay Minerals 37 297–307.CrossRefGoogle Scholar
Brindley, G.W. and Wardle, R., 1970 Monoclinic and triclinic forms of pyrophyllite and pyrophyllite anhydride American Mineralogist 55 1259–1272.Google Scholar
CrystalMaker®, 2012 Interactive visualization for crystal and molecular structures. Version 2.5.5 Oxford, England CrystalMaker Software Ltd.Google Scholar
Drits, V.A. Aleksandrova, V.A. Smolin, P.P., Kossovskaya, A.G., 1975 Refinement of the crystal structure of talc Crystal Chemistry of Minerals and Geological Problems Moscow Nauka 99–105.Google Scholar
Evans, B.W. and Guggenheim, S., 1988 Talc, pyrophyllite, and related minerals Hydrous Phyllosilicates Exclusive of Micas 19 225–294.CrossRefGoogle Scholar
Guggenheim, S. Adams, J.M. Bergaya, F. Brigatti, M.F. Drits, V.A. Formoso, M.L.L. Galán, E. Kogure, T. Stanjek, H. and Stucki, J.W., 2009 Nomenclature for stacking in phyllosilicates: Report of the Association Internationale pour l’Etude des Argiles (AIPEA) Nomenclature Committee for 2008 Clay Minerals 44 157–159.CrossRefGoogle Scholar
Kameda, J. Miyawaki, R. Kitagawa, R. and Kogure, T., 2007 XRD and HRTEM analyses of stacking structures in sudoite, di-trioctahedral chlorite American Mineralogist 92 1586–1592.CrossRefGoogle Scholar
Kogure, T. and Inoue, A., 2005 Determination of defect structures in kaolin minerals by high-resolution transmission electron microscopy (HRTEM) American Mineralogist 90 85–89.CrossRefGoogle Scholar
Kogure, T. Jige, M. Kamdeda, J. Yamgishi, A. Miyawaki, R. and Kitagawa, R., 2006 Stacking structures in pyrophyllite revealed by high resolution transmission electron microscopy (HRTEM) American Mineralogist 91 1293–1299.CrossRefGoogle Scholar
Kogure, T. Kameda, J. Matsui, T. and Miyawaki, R., 2006 Stacking structure in disordered talc: Interpretation of its X-ray diffraction pattern by using pattern simulation and high-resolution transmission electron microscopy American Mineralogist 91 1363–1370.CrossRefGoogle Scholar
Kogure, T. Kameda, J. and Drits, V.A., 2008 Stacking faults with 180° layer rotation in celadonite, iron and magnesium-rich dioctahedral mica Clays and Clay Minerals 56 612–621.CrossRefGoogle Scholar
Kogure, T. Elzea-Kogel, J. Johnston, C.T. and Bish, D.L., 2010 Stacking disorder in a sedimentary kaolinite Clays and Clay Minerals 58 62–71.CrossRefGoogle Scholar
Lee, J.H. and Guggenheim, S., 1981 Single crystal X-ray refinement of pyrophyllite-1Tc American Mineralogist 66 350–357.Google Scholar
Perdikatsis, B. and Burzlaff, H., 1981 Structurverfeinerung am Talk Mg3[(OH)2Si4O10] Zeitschrift für Kristallographie 156 177–186.Google Scholar
Plançon, A. Giese, R.F. Drits, V.A. and Bookin, A.S., 1989 Stacking faults in the kaolin-group minerals — defect structures of kaolinite Clays and Clay Minerals 37 203–210.CrossRefGoogle Scholar
Rayner, J.H. and Brown, G., 1973 Structure of talc Clays and Clay Minerals 21 103–114.CrossRefGoogle Scholar
Rothbauer, R., 1971 Untersuchung eines 2M1-Muskovits mit Neutronenstrahlen Neues Jahrbuch für Mineralogie Monatshefte 143–154.Google Scholar
Suitch, P.R. and Young, R.A., 1983 Atom positions in highly ordered kaolinite Clays and Clay Minerals 31 357–366.CrossRefGoogle Scholar
Wardle, R. and Brindley, G.W., 1972 The crystal structure of pyrophyllite, 1Tc, and its dehydroxylate American Mineralogist 57 732–750.Google Scholar
Zvyagin, B.B. Mishchenko, K.S. and Soboleva, S.V., 1969 Structure of pyrophyllite and talc in relation to the polytypes of mica-type minerals Soviet Physics/Crystallography 13 511–515.Google Scholar