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Crystal structure of KCaF3 determined by the Rietveld profile method

Published online by Cambridge University Press:  10 January 2013

Alicja Ratuszna,
Michel Rousseau and
Philippe Daniel
Alicja Ratuszna
Affiliation:
Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
Michel Rousseau
Affiliation:
Laboratoire de Physique de l'Etat Condense-URA CNRS No. 807, Université du Maine, Avenue Olivier Messien, 72017 Le Mans, France
Philippe Daniel
Affiliation:
Laboratoire de Physique de l'Etat Condense-URA CNRS No. 807, Université du Maine, Avenue Olivier Messien, 72017 Le Mans, France
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Abstract

Using the Rietveld profile method, the atomic coordinates and anisotropic temperature factors of KCaF3 were refined. At room temperature, KCaF3 crystallizes in monoclinic B21/m symmetry, with the lattice parameters: a=8.754(2) Å, b=8.765(4) Å, c=8.760(5) Å, β=90.48(3)°, V=672.1(3) Å3, Z=8. The refinement procedure was stopped when RB=0.05 and the Durbin–Watson statistic factor=0.85 had been reached. The structure determined is related to the tilting of CaF6 octahedra of the a−b+c− type, which are responsible for the monoclinic distortion in perovskite crystals.

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Type
Research Article
Information
Powder Diffraction , Volume 12 , Issue 2 , June 1997, pp. 70 - 75
Copyright
Copyright © Cambridge University Press 1997

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