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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

Information

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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References

Alonso, J. A., Martinez-Lope, M. J., Casais, M. T., and Fernández-Diaz, M. T. (2000). “Evolution of the Jahn-Teller distortion of MnO6 octahedra in RMnO3 perovskites (R=Pr, Nd, Dy, Tb, Ho, Er, Y): A neutron diffraction study,” Inorg. Chem. INOCAJ 39, 917–923CrossRefGoogle Scholar
Brese, N. E. and O’Keeffe, M. (1991). “Bond-valence parameters for solids,” Acta Crystallogr., Sect. B: Struct. Sci. ASBSDK B47, 192–197.CrossRefGoogle Scholar
Brinks, H. W., Fjellvåg, H., and Kjekshus, A. (1997). “Synthesis of metastable perovskite-type YMnO3 and HoMnO3,” J. Solid State Chem. JSSCBI 129, 334–340.Google Scholar
Brown, I. D. (1989). “A determination of the oxidation states and internal stresses in Ba2YCu3Ox, x=6−7 using bond valences,” J. Solid State Chem. JSSCBI 82, 122–131.Google Scholar
Glazer, A. M. (1975). “Simple ways of determining perovskite structures,” Acta Crystallogr., Sect. A: Cryst. Phys., Diffr., Theor. Gen. Crystallogr. ACACBN A31, 756–762.Google Scholar
Lufaso, M. W. and Woodward, P. M. (2004). “Jahn–Teller distortion, cation ordering and octahedral tilting in perovskites,” Acta Crystallogr., Sect. B: Struct. Sci. ASBSDK B60, 10–20.CrossRefGoogle Scholar
Poeppelmeier, K. R., Leonowicz, M. E., Scanlon, J. C., Longo, J. M., and Yelon, W. B. (1982). “Structure determination of CaMnO3 and CaMnO2.5 by X-ray and neutron methods,” J. Solid State Chem. JSSCBI 45, 71–79.Google Scholar
Rao, G. H., Bärner, K., and Brown, I. D. (1998). “Bond-valence analysis on the structural effects in magnetoresistive manganese perovskites,” J. Phys.: Condens. Matter JCOMEL 10, L757–L763.Google Scholar
Shannon, R. D. (1976). “Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides,” Acta Crystallogr., Sect. A: Cryst. Phys., Diffr., Theor. Gen. Crystallogr. ACACBN A32, 751–767.Google Scholar
Toulemonde, O., Studer, F., Barnabé, A., Maignan, A., Martin, C., and Raveau, B. (1998). “Charge states of transition metal in Cr, Co and Ni doped Ln0.5Ca0.5O3 CMR manganites,” Eur. Phys. J. B EPJBFY 4, 159–167.Google Scholar
Waintal, A. and Chenavas, J. (1967). “Transformation sous haute pression de la forme hexagonale de MnT′O3, (T′=Ho Er, Tm, Yb, Lu) en une forme perovskite,” Mater. Res. Bull. MRBUAC 2, 819–822.CrossRefGoogle Scholar
Yakel, H. L., Koehler, W. C., Bertaut, E. F., and Forrat, E. F. (1963). “On the crystal structure of the manganese (III) trioxides of the heavy lanthanides and yttrium,” Acta Crystallogr. ACCRA9 16, 957–962.CrossRefGoogle Scholar
Young, R. A. (1993). The Rietveld Method, edited by Young, R. A., Ed, IUCr Monographs on Crystallography Vol. 5 (Oxford University Press, Oxford), pp. 1–38.CrossRefGoogle Scholar