Ferroelectrics · 2008 · 50 citations · 7 references
Natural SciencesMaterials SciencePhysicsCondensed Matter PhysicsMagnetic MaterialsSolid State PhysicsAntiferromagnetismMagnetic Properties Of SolidsMagnetism In SolidsMultiferroic MaterialsMössbauer SpectroscopyPhase TransitionsDielectric PermittivityMagnetic PerovskitesMagnetic Phase TransitionsMultiferroic PerovskitesOxide PerovskitesPartial OrderingPermittivityPerovskite Dielectrics
Mossbauer spectra studies were used to determine the temperatures of magnetic phase transitions in some Fe-containing perovskite multiferroics and their solid solutions. In compositionally disordered materials the temperature TN of antiferromagnetic phase transition depends linearly on Fe3+ content. Partial ordering of Fe3+ and B5+ cations in Pb(Fe1/2B1/2)O3 (B = Nb, Ta) ternary perovskites decreases TN by more than 50 K. At the same time the temperature T m of dielectric permittivity maximum remains unchanged for Pb(Fe1/2Nb1/2)O3 and increases for Pb(Fe1/2Ta1/2)O3. These results are in line with existing theoretical models of B-cation ordering effect on TN and T m values in PbB3+ 1/2B5+ 1/2O3 perovskites.
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