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New neutron time-of-flight (TOF) capability in PDF-4+ relational databases: digitized diffraction patterns and I/Ic for quantitative phases analysis

Published online by Cambridge University Press:  03 May 2017

J. Faber ,
S. Kabekkodu ,
J. Blanton ,
T. Blanton  and
T. Fawcett
J. Faber*
Affiliation:
Faber Consulting, Thornton, Pennsylvania
S. Kabekkodu
Affiliation:
International Centre for Diffraction Data (ICDD), Newtown Square, Pennsylvania
J. Blanton
Affiliation:
International Centre for Diffraction Data (ICDD), Newtown Square, Pennsylvania
T. Blanton
Affiliation:
International Centre for Diffraction Data (ICDD), Newtown Square, Pennsylvania
T. Fawcett
Affiliation:
International Centre for Diffraction Data (ICDD), Newtown Square, Pennsylvania
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected]
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Abstract

The PDF-4+ 2016 contains 271 449 entries with atomic coordinates that can be used to calculate neutron time-of-flight (TOF) powder diffraction patterns. These diffraction patterns can all be calculated on-the-fly. Three TOF results can be realized: the live calculation of on-the fly diffraction patterns, the population of static PDF® entries, and data for search/match tables for phase identification. In connection with search/match, we have extended the development of the I/Ic formalism to include both constant wavelength (CW) and TOF neutron diffraction data. It is shown that the wavelength dependence of X-ray and CW neutron data must be factored into the behavior of I/Ic, whereas this dependence is directly incorporated into TOF data.

Keywords

time-of-flight (TOF) neutron powder diffractionI/Ic for quantitative phases analysisPDF-4+ relational database
Type
Technical Articles
Information
Powder Diffraction , Volume 32 , Issue 2 , June 2017 , pp. 107 - 111
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Copyright
Copyright © International Centre for Diffraction Data 2017 

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