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Title: The mechanism of reequilibration of solids in the presence of a fluid phase

Abstract

The preservation of morphology (pseudomorphism) and crystal structure during the transformation of one solid phase to another is regularly used as a criterion for a solid-state mechanism, even when there is a fluid phase present. However, a coupled dissolution-reprecipitation mechanism also preserves the morphology and transfers crystallographic information from parent to product by epitaxial nucleation. The generation of porosity in the product phase is a necessary condition for such a mechanism as it allows fluid to maintain contact with a reaction interface which moves through the parent phase from the original surface. We propose that interface-coupled dissolution-reprecipitation is a general mechanism for reequilibration of solids in the presence of a fluid phase. - Graphical abstract: A single crystal of KBr is transformed to a porous single crystal of KCl by immersion in saturated KCl solution. The image shows partial transformation of a crystal of KBr (core) to KCl (porous, milky rim) by an interface coupled dissolution-reprecipitation mechanism. The external dimensions and crystallographic orientation of the original crystal are preserved, while a reaction interface moves through the crystal.

Authors:
 [1];  [2]
  1. Institut fuer Mineralogie, University of Muenster, Corrensstrasse 24, 48149 Muenster (Germany), E-mail: putnis@uni-muenster.de
  2. Institut fuer Mineralogie, University of Muenster, Corrensstrasse 24, 48149 Muenster (Germany)
Publication Date:
OSTI Identifier:
21015837
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 180; Journal Issue: 5; Other Information: DOI: 10.1016/j.jssc.2007.03.023; PII: S0022-4596(07)00125-9; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CRYSTAL STRUCTURE; CRYSTAL-PHASE TRANSFORMATIONS; CRYSTALLOGRAPHY; DISSOLUTION; EPITAXY; FLUIDS; INTERFACES; MONOCRYSTALS; MORPHOLOGY; POROSITY; POROUS MATERIALS; POTASSIUM BROMIDES; POTASSIUM CHLORIDES; PRESERVATION; SOLVENTS

Citation Formats

Putnis, Andrew, and Putnis, Christine V. The mechanism of reequilibration of solids in the presence of a fluid phase. United States: N. p., 2007. Web. doi:10.1016/j.jssc.2007.03.023.
Putnis, Andrew, & Putnis, Christine V. The mechanism of reequilibration of solids in the presence of a fluid phase. United States. doi:10.1016/j.jssc.2007.03.023.
Putnis, Andrew, and Putnis, Christine V. Tue . "The mechanism of reequilibration of solids in the presence of a fluid phase". United States. doi:10.1016/j.jssc.2007.03.023.
@article{osti_21015837,
title = {The mechanism of reequilibration of solids in the presence of a fluid phase},
author = {Putnis, Andrew and Putnis, Christine V.},
abstractNote = {The preservation of morphology (pseudomorphism) and crystal structure during the transformation of one solid phase to another is regularly used as a criterion for a solid-state mechanism, even when there is a fluid phase present. However, a coupled dissolution-reprecipitation mechanism also preserves the morphology and transfers crystallographic information from parent to product by epitaxial nucleation. The generation of porosity in the product phase is a necessary condition for such a mechanism as it allows fluid to maintain contact with a reaction interface which moves through the parent phase from the original surface. We propose that interface-coupled dissolution-reprecipitation is a general mechanism for reequilibration of solids in the presence of a fluid phase. - Graphical abstract: A single crystal of KBr is transformed to a porous single crystal of KCl by immersion in saturated KCl solution. The image shows partial transformation of a crystal of KBr (core) to KCl (porous, milky rim) by an interface coupled dissolution-reprecipitation mechanism. The external dimensions and crystallographic orientation of the original crystal are preserved, while a reaction interface moves through the crystal.},
doi = {10.1016/j.jssc.2007.03.023},
journal = {Journal of Solid State Chemistry},
number = 5,
volume = 180,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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