An X-ray diffraction, magnetic susceptibility and spectroscopic studies of Yb{sub 2-x}Cr{sub x}O{sub 3}

Journal Article · Fri Jul 15 00:00:00 EDT 2011 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2011.05.022· OSTI ID:21580126

Hamdi, S; Amami, M ^[1]; Hlil, E K ^[2]

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1. Unite de Recherche de Chimie des Materiaux, ISSBAT, Universite Tunis ElManar, 9 Avenue Dr. Zouhaier Safi, 1006 Tunis (Tunisia)
2. Institut Neel CNRS, Departement MCMF, B.P. 166, 38042 Grenoble Cedex 9 (France)

Polycrystalline samples with general formula Yb{sub 2-x}Cr{sub x}O{sub 3} (0<x<0.03), obtained by sol-gel method and analyzed by X-ray diffraction, formed solid solutions over all the mentioned range. Cr showed a maximum solubility of 2.8 mol% in Yb{sub 2}O{sub 3} sesquioxide at 1000 deg. C. A preferential substitution of Cr{sup 3+} ions over two cationic sites, 8b and 24d in the space group Ia-3 was found. The lattice parameters a are found to vary linearly (10.4402(4) A <a<10.4372(1) A) with the composition x. The two independent atoms Yb/Cr have octahedral coordination; however, the degrees of distortion of their coordination polyhedron are different. Replacing Yb{sup 3+} by Cr{sup 3+} introduces slight changes in the atomic coordinates leading to an increase of the mean cation-anion distances. The ability of Raman spectroscopy to detect changes in local coordination is utilized. A pseudo-tetrahedral coordination for the Cr{sup 3+} in the 24d site was found. Magnetic susceptibility measurements of all samples were done in a temperature range of 2-50 K. For T<37 K, the inverse paramagnetic susceptibilities depend linearly on temperature. However, in the high-temperature region, for T>37 K, the inverse paramagnetic susceptibilities are non-linear versus temperature. This deviation from the Curie-Weiss behaviour was discussed. - Graphical abstract: The least square fit to the modified Curie-Weiss law shows paramagnetic interaction in Yb{sub 2-x}Cr{sub x}O{sub 3} (0<x{<=}0.03). The YbCrO{sub 3} phase impurity will have no influence on the magnetic properties of the samples with x>0.03 Highlights: > We described our attempts to synthesize Yb{sub 2-x}Cr{sub x}O{sub 3} series of compounds.{yields} The products were characterized by X-ray diffraction, Raman and magnetic measurements. > Cr showed a maximum solubility of 2.8 mol% in Yb{sub 2}O{sub 3} sesquioxide at 1000 deg. C. > The least square fit to the modified Curie-Weiss law shows paramagnetic interaction. > The YbCrO{sub 3} phase impurity has no influence on the magnetic properties of the samples.

• OSTI ID: 21580126
• Journal Information: Journal of Solid State Chemistry, Vol. 184, Issue 7; Other Information: DOI: 10.1016/j.jssc.2011.05.022; PII: S0022-4596(11)00271-4; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CHROMIUM IONS
CURIE-WEISS LAW
IMPURITIES
INTERACTIONS
LATTICE PARAMETERS
LEAST SQUARE FIT
MAGNETIC SUSCEPTIBILITY
PARAMAGNETISM
POLYCRYSTALS
RAMAN SPECTROSCOPY
SOL-GEL PROCESS
SOLID SOLUTIONS
SOLUBILITY
SPACE GROUPS
TEMPERATURE RANGE 0400-1000 K
X-RAY DIFFRACTION
YTTERBIUM IONS
YTTERBIUM OXIDES
CHALCOGENIDES
CHARGED PARTICLES
COHERENT SCATTERING
CRYSTALS
DIFFRACTION
DISPERSIONS
HOMOGENEOUS MIXTURES
IONS
LASER SPECTROSCOPY
MAGNETIC PROPERTIES
MAGNETISM
MATHEMATICAL SOLUTIONS
MAXIMUM-LIKELIHOOD FIT
MIXTURES
NUMERICAL SOLUTION
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SCATTERING
SOLUTIONS
SPECTROSCOPY
SYMMETRY GROUPS
TEMPERATURE RANGE
YTTERBIUM COMPOUNDS