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A New Computer Algorithm for Qualitative X-Ray Powder Diffraction Analysis

Published online by Cambridge University Press:  06 March 2019

T. C. Huang
Affiliation:
IBM Research Laboratory San Jose, California 95193
W. Parrish
Affiliation:
IBM Research Laboratory San Jose, California 95193
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Abstract

An effective and practical computer algorithm has been developed for rapid and precise phase identification of polycrystalline materials by X-ray diffraction methods using the JCPDS database and/or user created standard files. The entire JCPDS file was reorganized for efficient search. Identifications are facilitated by a number of options: automatic correction of systematic errors using internal standard reflections, selectable window widths for file searching, elemental restrictions (chemical prescreening), handling preferred orientation, match without using intensities, match with 3 reflections, and others. A comprehensive algorithm for calculating a figure-of-merit (FOM) is used so that the “correct” phases can easily be identified with highest FOMs. This method has been tested extensively on a wide variety of analyses and is applicable to either a host or a minicomputer.

Type
VI. XRD Search/Match Procedures and Automation
Copyright
Copyright © International Centre for Diffraction Data 1981

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