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Lattice parameter measurement using Le Bail versus structural (Rietveld) refinement: A caution for complex, low symmetry systems

Published online by Cambridge University Press:  01 March 2012

V. K. Peterson*
Affiliation:
University of Technology, Sydney, Australia
*
a)Electronic mail: vanessa.peterson@nist.gov

Abstract

The measurement of lattice parameters using the Le Bail method was shown to be inappropriate for a complex, low symmetry, structure, even with high resolution synchrotron diffraction data. The method failed as a result of ambiguous indexing in the absence of constraints on diffraction intensities, that arise when a structural model is used, combined with the large number of reflections. A caution for the use of the Le Bail and other whole-powder pattern decomposition methods is presented, particularly for high reflection density data.

Type
Technical Articles
Copyright
Copyright © Cambridge University Press 2005

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