Journal of the Physical Society of Japan · 1994 · 33 citations · 4 references
Natural SciencesMaterials SciencePhysicsCondensed Matter PhysicsCrystal StructureSolid State PhysicsAntiferromagnetismCrystal ChemistryCrystal LatticeCrystal SymmetryFerroelectric MaterialsPhase TransitionsCrystal Lattice SymmetryFerroelectric CrystalsFerroelectric Phase TransitionsFerroelectric PropertiesFerroelectricityHexagonal SymmetryPhase Transition TemperatureStructural Phase Transitions
A hexagonal antiferromagnet RbFeBr 3 was found to undergo successive structural phase transitions at T I (=109.0 K) and T c (=34.4 K) and to be ferroelectric along the hexagonal c -axis below T c . RbFeBr 3 is a new type of ferroelectric crystal, the crystal structure of which is characterized by linear chains of face-sharing octahedra (FeBr 6 ) 4- along the c -axis (h-h-h packing). The ferroelectricity in RbFeBr 3 is attributed to possible shifts of two-thirds of the chains antiparallel to the remaining one-third along the c -axis, which are possible due to the crystal symmetry of P 6 3 c m below T c .
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