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Full pattern comparison of experimental and calculated powder patterns using the Integral Index method in PDF-4+

Published online by Cambridge University Press:  29 February 2012

John Faber*
Affiliation:
International Centre for Diffraction Data, Newtown Square, Pennsylvania 19073-3273
Justin Blanton
Affiliation:
International Centre for Diffraction Data, Newtown Square, Pennsylvania 19073-3273
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected]

Abstract

Quantitative comparisons between patterns from PDF-4 and experimental data using the Integral Index method are presented. The software integrated into the PDF-4 (DDView+) provides the ability to calculate fully digitized diffraction patterns for all 272,232 entries (PDF-4+ 2007). To provide a means of quantitative comparison between entries in the Power Diffraction File (PDF) and experimental data obtained in the laboratory, data filtering using Boolean logic has been used to reduce the size of the comparison set. Within this comparison set, we have used the Integral Index method to provide quantitative comparisons between digitized patterns obtained from the PDF-4 and experimental data. The quantitative aspects facilitate total pattern matching, that is, selecting the pattern in the PDF-4 that most closely matches input experimental data. Several examples will be used to illustrate the pattern matching process and the utility of this approach will be examined.

Type
X-Ray Diffraction
Copyright
Copyright © Cambridge University Press 2008

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