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The crystal structure of (Ho0.50Ca0.50)MnO3 and its evolution with Cr doping: A Rietveld refinement investigation

Published online by Cambridge University Press:  01 March 2012

A. Martinelli  and
M. Ferretti
A. Martinelli*
Affiliation:
INFM-LAMIA, C. so Perrone 24, 16152 Genova, Italy
M. Ferretti
Affiliation:
INFM-LAMIA, C. so Perrone 24, 16152 Genova, Italy and Dip. Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso 31, 16146 Genova, Italy
*
a)Electronic mail: amartin@chimica.unige.it
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Abstract

Single-phase (Ho0.50Ca0.50)MnO3 has been successfully prepared by means of solid state reaction at high temperature. Its crystal structure, as well as those of Cr-doped samples(Ho1−xCax)(Mn1−yCry)O3, has been refined by the Rietveld method, using X-ray powder diffraction data. All the examined compounds crystallize in the Pnma space group with a distorted perovskite-type structure. The distortion of the BO6 octahedra, due to the Jahn–Teller Mn3+ ionic species, decreases with the Cr content. Bond valence sum calculations were carried out using the refined results.

Keywords

(Ho0.50Ca0.50)MnO3manganiteX-ray powder diffractionRietveld methodbond valence sum method
Type
Technical Articles
Information
Powder Diffraction , Volume 20 , Issue 1 , March 2005 , pp. 22 - 26
Copyright
Copyright © Cambridge University Press 2005

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