Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Sakharov, B. A. Articles by Drits, V. A. Search for Related Content GeoRef GeoRef Citation

INFLUENCE OF THE OUTER SURFACE LAYERS OF CRYSTALS ON THE X-RAY DIFFRACTION INTENSITY OF BASAL REFLECTIONS

¹ Geological Institute, Russian Academy of Sciences, 7 Pyzhevsky Street, 119017 Moscow, Russia
² Crystallography Laboratory, ISTO, University of Orléans – CNRS, 45067 Orléans Cedex 2, France
³ Environmental Geochemistry Group, LGIT – Maison des GéoSciences, CNRS – University of Grenoble, 38041 Grenoble Cedex 9, France

^* E-mail address of corresponding author: bruno.lanson{at}obs.ujf-grenoble.fr

This study presents a mathematical formalism describing diffraction effects from periodic and mixed-layer minerals in which the outer surface layers of crystals possibly differ from layers forming the core of the crystals. The X-ray diffraction (XRD) patterns calculated for structure models of chlorite and irregular chlorite-smectites terminated on both sides of the crystals by either brucite-like sheets or 2:1 layers show the strong influence that different outer surface layers have on the distribution of basal reflection intensities. Simulation of the experimental XRD patterns from two chlorite samples having different Fe contents shows that in these two samples the chlorite crystals were terminated by brucite-like sheets on both sides. In contrast, crystals in a corrensite sample were terminated by water molecules and exchangeable cations. The nature of diffraction effects due to outer surface layers is discussed.

Key Words: Basal Reflections • Brucite Sheets • Chlorite • Corrensite • Mixed-layer Structures • Outer Surface Layers • XRD

This article has been cited by other articles:

				I. M. Kang, M. H. Kim, and H.-S. Moon Finding the layer scattering origin of rectorite for basal peak calculations American Mineralogist, October 1, 2009; 94(10): 1411 - 1416. [Abstract] [Full Text] [PDF]