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Crystal structure of Nd2−xMxRu2O7−y (M=Cu, Ag) pyrochlores by X-ray powder diffraction

Published online by Cambridge University Press:  01 March 2012

G. Kimmel ,
H. On ,
D. Itzhak  and
J. Hormadaly
G. Kimmel
Affiliation:
Institutes for Applied Research, Ben-Gurion University of the Negev, P.O. Box 653, 84105 Beer-Sheva, Israel
H. On
Affiliation:
Materials Engineering Department, Ben-Gurion University of the Negev, P.O. Box 653, 84105 Beer-Sheva, Israel
D. Itzhak
Affiliation:
Materials Engineering Department, Ben-Gurion University of the Negev, P.O. Box 653, 84105 Beer-Sheva, Israel
J. Hormadaly
Affiliation:
Zandman Center for Thick Film Microelectronics and Chemistry Department, Ben-Gurion University of the Negev, P.O. Box 653, 84105 Beer-Sheva, Israel
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Abstract

The crystal structures of ruthenium oxides with the general formula Nd2−xMxRu2O7−y, where M is Cu or Ag, 0≤x≤0.25, were investigated. All compounds that were prepared exhibit the pyrochlore structure with a cubic unit cell. The compounds were characterized by X-ray powder diffraction, and single-phase structures were found for Nd2−xCuxRu2O7−y, x=0.1, 0.2, 0.25, and for Nd2−xAgxRu2O7−y, x=0.1, 0.15, 0.2. The relative metal concentrations were verified by EDS. The cell parameters were determined by advanced peak-position analysis and calibrated by a Si internal standard. Atomic positions and oxygen occupancies where refined by the Rietveld method. It was found that the cell-size modifications agree with the relations between ionic sizes.

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Type
Technical Articles
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Powder Diffraction , Volume 22 , Issue 3 , September 2007 , pp. 231 - 235
Copyright
Copyright © Cambridge University Press 2007

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