Antiferromagnetic ordering and structural characterization of the brown colored R[sub 2]BaCoO[sub 5] oxides (R = rare earth)

Journal Article · Wed Jun 01 04:00:00 EDT 1994 · Journal of Solid State Chemistry; (United States)

DOI:https://doi.org/10.1006/jssc.1994.1175· OSTI ID:6656302

Hernandez-Velasco, J; Salinas-Sanchez, A; Saez-Puche, R ^[1]

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1. Universidad Complutense de Madrid (Spain)

New R[sub 2]BaCoO[sub 5] oxides (R = rare earth) have been prepared in Ar flow, and the X-ray diffraction data reveal that they crystallize in the Nd[sub 2]BaNiO[sub 5] structural type (space group Immm). The existence of dimorphism has been shown for R = Dy, Ho, Er, and Tm. A comparative study of the influence of the rare earth size on the structural parameters is presented for this family of compounds. The relative stability of these oxides is discussed from the variation of the so-called global instability index (GII) calculated using the bond valence method. The GII values around 0.2 v.u. are indicative of the high stress present in this structure. The magnetic properties of these oxides have been studied from magnetic susceptibility measurements and one-dimensional antiferromagnetic correlations in the Co[sup +2] sublattice are presented around the room temperature, while three-dimensional antiferromagnetic interactions in both R[sup +3] and Co[sup +2] sublattices have been observed at lower temperatures (T[sub Neel] < 40 K) in this family of oxides. This behavior is explained considering the crystal structure of these compounds and the electronic states of the Co[sup +2] and R[sup +3] cations.

• OSTI ID: 6656302
• Journal Information: Journal of Solid State Chemistry; (United States), Journal Name: Journal of Solid State Chemistry; (United States) Vol. 110:2; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
&amp; Refractories-- Structure &amp; Phase Studies
360204 -- Ceramics
Cermets
&amp; Refractories-- Physical Properties
ALKALINE EARTH METAL COMPOUNDS
ANTIFERROMAGNETISM
BARIUM COMPOUNDS
CHALCOGENIDES
CHEMICAL PREPARATION
COBALT COMPOUNDS
ELECTRONIC STRUCTURE
MAGNETIC PROPERTIES
MAGNETIC SUSCEPTIBILITY
MAGNETISM
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RARE GAS COMPOUNDS
STRUCTURAL CHEMICAL ANALYSIS
SYNTHESIS
TRANSITION ELEMENT COMPOUNDS