Oxides of the type YbMn1-xFexO3; x≤0.3 showing multiferroic behavior have been synthesized by the solid state route. These oxides crystallize in the hexagonal structure known for the parent YbMnO3 with the c/a ratio increasing with Fe substitution. The distortion of the MnO5 polyhedra (tbp) decreases and the Mn-O-Mn bonds in the a-b plane become shorter with Fe-substitution. Magnetic ordering is observed from the low temperature neutron diffraction study. The compounds were found to be antiferromagnetic and the ordering temperature TN increased from 82 K for pure YbMnO3 to 95 K for YbMn0.7Fe0.3O3. Variable temperature dielectric measurements (15-110 K) show an anomaly in the dielectric constant at temperatures close to the antiferromagnetic ordering temperature for all the compositions, showing a unique correlation between the magnetic and electric field. The increase in the ordering temperature in YbMn1-xFexO3 is explained on the basis of increase in covalence of Mn/Fe-O-Mn/Fe bonds (shorter) with iron substitution.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry