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Some further considerations in powder diffraction pattern indexing with the dichotomy method

Published online by Cambridge University Press:  17 November 2014

Daniel Louër*
Affiliation:
Retired from Centre National de la Recherche Scientifique and Université de Rennes 1, France
Ali Boultif
Affiliation:
Faculté des Sciences Exactes, Département de Physique, Laboratoire de Cristallographie, Université de Constantine 1, 25000 Constantine, Algeria
*
a)Author to whom correspondence should be addressed. Electronic mail: daniel.louer@free.fr

Abstract

Some improvements have been introduced in the current computer program for powder diffraction pattern indexing using the dichotomy algorithm. The resulting version, DICVOL14, includes optimizations and extension of scanning limits for triclinic cases, a detailed review of the input data from the indexing solutions, cell centering tests and a new approach for zero-point offset evaluation. The performance of the new version is illustrated with many examples, such as triclinic cases with long axes and dominant zones. Some important parameters in pattern indexing based on the dichotomy algorithm are commented upon, e.g. the precision of data and spurious lines.

Type
Technical Articles
Copyright
Copyright © International Centre for Diffraction Data 2014 

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