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Typical values of Rietveld instrument profile coefficients

Published online by Cambridge University Press:  05 March 2012

James A. Kaduk*
Affiliation:
Illinois Institute of Technology, 3101 S. Dearborn St., Chicago, Illinois 60616
Joel Reid
Affiliation:
International Centre for Diffraction Data, 12 Campus Blvd., Newtown Square, Pennsylvania 19073
*
a)Author to whom correspondence should be addressed. Electronic mail: kaduk@polycrystallography.com

Abstract

GSAS instrument parameters are tabulated for a variety of laboratory and synchrotron diffractometers to give users an idea of the typical ranges of profile parameters when they generate their own instrument parameter files. For modern high-resolution laboratory diffractometers, the parameters fall in the ranges 0<U<3, V=0, 0<W<4, 1<X<3, 0<Y<3, 1<asym<3, and 0<S/L<0.03. For synchrotron diffractometers, the parameters fall in the ranges 0<U<1.2, −1<V<0, 0<W<1, 0<X<1, 0<Y<1, 0<asym<0.5, 0<S/L<0.001, and 0<H/L<0.007. FULLPROF equivalents are also reported. The factors which are convoluted together to generate the instrument profile are described.

Type
Crystallography Education
Copyright
Copyright © Cambridge University Press 2011

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