Layered Mineral Structures and their Application in Advanced Technologies

This volume covers the topics related to the 13th EMU School ‘Layered Mineral Structures and their Application in Advanced Technologies’. All of the selected topics, the school, and this volume are thus aimed at providing an in-depth knowledge of the complex field of layered materials, with an attempt to address several fundamental aspects, which range from crystal chemistry and structure to layer packing disorder, from surface properties to the description of the most advanced experimental techniques useful in the characterization of layered materials. Layered materials, because of their particular atomic arrangement, are commonly characterized by physical and chemical properties of great interest in numerous technological and environmental processes and applications, as better detailed in the body of this volume. Most of these properties play a significant role in Earth sciences, environmental sciences, technology, biotechnology, material sciences and many other scientific areas. The surface properties of layered materials control important interaction processes, such as coagulation, aggregation, sedimentation, filtration, catalysis and ionic transport in porous media. Layered minerals also control many aspects of Earth's rheology, i.e. the movement of geological masses, at least as far down as the lower crust. Given this frameset, it should be no surprise that the extremely large field of investigation of these materials can, and in most of the cases must, be approached from several different viewpoints. However, providing full coverage of the immense literature devoted to all the topics above may be impractical, if not impossible.
Modelling of X-ray diffraction profiles: Investigation of defective lamellar structure crystal chemistry
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Published:January 01, 2011
Abstract
Layered minerals and materials are ubiquitous and characterized by the frequent occurrence of stacking defects. In particular, interstratification (or mixed layering), which corresponds to the intimate intergrowth of layers differing in terms of their layer thickness and/or internal structure, and stacking faults, both random and well defined, are especially common. These defects impact heavily on the reactivity of the lamellar structures. In addition, they may record the conditions of mineral (trans)formation. Determining their nature, abundance and possibly their distribution is thus an essential step in their structural characterization leading to an understanding of their reactivity. Over recent decades, modelling of X-ray diffraction profiles has proved to be an important tool which allows detailed structural identification of defective lamellar structures. The present chapter will review the basic concepts of such identification and review the literature to outline how our understanding of defective structures and mixed layers has improved over the last decade or so and to describe some of the new perspectives opened by this improvement.