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A novel powder diagrams indexing, using classical geometry

Published online by Cambridge University Press:  30 November 2012

M.L. Ettorche*
Affiliation:
Laboratoire de Cristallographie, Département de Physique, Faculté des Sciences, Université Mentouri Constantine, Route Ain El Bey, Constantine 25000, Algeria
M. Sebais
Affiliation:
Laboratoire de Cristallographie, Département de Physique, Faculté des Sciences, Université Mentouri Constantine, Route Ain El Bey, Constantine 25000, Algeria
Z. Hammoudi
Affiliation:
Laboratoire Signaux et Systèmes de Communication, Département d'Electronique, Faculté de Sciences de l'ingénieur, Université Mentouri Constantine, Route Ain El Bey, Constantine 25000, Algeria
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected]

Abstract

Based only on a geometrical approach, we present a technique to index powder diffraction diagrams. This would allow us to find the cell parameters from the experimental data. It is well known that methods proposed in the literature make a direct use of the experimental data to build the cell, whereas our approach exploits them to calculate theoretical values, which could be multiples of two of the three vectors' lengths of the unit cell, and then uses them along with the experimental values. To show the effectiveness of the proposed algorithm, several examples, requiring only minor limitations in linear dimensions (<35 Å) and volume (<4500 Å3), are treated. For all considered cases, except the triclinic symmetry that is time consuming, the corresponding FORTRAN routine is executed in a reasonable time (<3 min with a 3 GHz processor).

Type
Technical Articles
Copyright
Copyright © International Centre for Diffraction Data 2012

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