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Title: The evolution of structural changes in ettringite during thermal decomposition

Abstract

The thermal decomposition of ettringite, Ca{sub 6}[Al(OH){sub 6}]{sub 2}(SO{sub 4}){sub 3}.{approx}26H{sub 2}O, was studied with pulsed neutron time-of-flight diffraction combined with Rietveld structure refinement. Like prior investigations, transition from a crystalline to amorphous state occurred following the loss of {approx}20 water molecules. In contrast to earlier investigations, which relied upon indirect measurements of water and hydroxyl occupancies, the present study inferred the occupancies directly from Rietveld crystal structure refinement of the diffraction data. The decomposition pathway was shown to be more complex than previously envisioned, involving the simultaneous loss of hydroxyl and water molecules. Nuclear magnetic resonance (NMR) spectroscopy studies of the rigid lattice lineshapes of fully and partially hydrated ettringite were performed and confirmed our decomposition model.

Authors:
 [1];  [2];  [3];  [2]
  1. University of Michigan, Ann Arbor, MI 48109 (United States). E-mail: michael.hartman@nist.gov
  2. Department of Physics, Washington University, CB 1105, St. Louis, MO 63130 (United States)
  3. University of Michigan, Ann Arbor, MI 48109 (United States)
Publication Date:
OSTI Identifier:
20784983
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 179; Journal Issue: 4; Other Information: DOI: 10.1016/j.jssc.2006.01.038; PII: S0022-4596(06)00043-0; Copyright (c) 2006 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; ALUMINATES; AMORPHOUS STATE; CALCIUM COMPOUNDS; CEMENTS; CRYSTAL STRUCTURE; HYDROXIDES; NEUTRON DIFFRACTION; NUCLEAR MAGNETIC RESONANCE; PHYSICAL PROPERTIES; SPECTROSCOPY; SULFATES; TIME-OF-FLIGHT METHOD

Citation Formats

Hartman, Michael R., Brady, Steven K., Berliner, Ronald, and Conradi, Mark S. The evolution of structural changes in ettringite during thermal decomposition. United States: N. p., 2006. Web. doi:10.1016/j.jssc.2006.01.038.
Hartman, Michael R., Brady, Steven K., Berliner, Ronald, & Conradi, Mark S. The evolution of structural changes in ettringite during thermal decomposition. United States. doi:10.1016/j.jssc.2006.01.038.
Hartman, Michael R., Brady, Steven K., Berliner, Ronald, and Conradi, Mark S. Sat . "The evolution of structural changes in ettringite during thermal decomposition". United States. doi:10.1016/j.jssc.2006.01.038.
@article{osti_20784983,
title = {The evolution of structural changes in ettringite during thermal decomposition},
author = {Hartman, Michael R. and Brady, Steven K. and Berliner, Ronald and Conradi, Mark S.},
abstractNote = {The thermal decomposition of ettringite, Ca{sub 6}[Al(OH){sub 6}]{sub 2}(SO{sub 4}){sub 3}.{approx}26H{sub 2}O, was studied with pulsed neutron time-of-flight diffraction combined with Rietveld structure refinement. Like prior investigations, transition from a crystalline to amorphous state occurred following the loss of {approx}20 water molecules. In contrast to earlier investigations, which relied upon indirect measurements of water and hydroxyl occupancies, the present study inferred the occupancies directly from Rietveld crystal structure refinement of the diffraction data. The decomposition pathway was shown to be more complex than previously envisioned, involving the simultaneous loss of hydroxyl and water molecules. Nuclear magnetic resonance (NMR) spectroscopy studies of the rigid lattice lineshapes of fully and partially hydrated ettringite were performed and confirmed our decomposition model.},
doi = {10.1016/j.jssc.2006.01.038},
journal = {Journal of Solid State Chemistry},
number = 4,
volume = 179,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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