REVIEW: Phase transitions in BaMnF4
Abstract
The physical characteristics of BaMnF4, a pyroelectric ferromagnet, are surveyed. It has the only known continuous antiferroelectric phase transition. Attention is given to such features as the two- and three-dimensional anti-ferromagnetic ordering temperatures, and the exhibition of dielectric anomalies at its Neel temperature. In addition, it is the only known case of a weak ferromagnet with ferromagnetism caused by the linear magnetoelectric effect. At high temperatures its dielectric constant diverges with increasing temperature; a ferroelectric phase transition would occur if the crystals did not melt first. Finally, theory and experiment for this material are reviewed, including neutron, Raman and Brillouin scattering; X-ray, dielectric and conductivity measurements; magnetic resonance and susceptibility studies.
- Publication:
-
Reports on Progress in Physics
- Pub Date:
- June 1979
- DOI:
- 10.1088/0034-4885/42/6/003
- Bibcode:
- 1979RPPh...42.1055S
- Keywords:
-
- Barium Fluorides;
- Ferromagnetic Materials;
- Manganese Compounds;
- Phase Transformations;
- Antiferromagnetism;
- Brillouin Effect;
- Dielectric Properties;
- High Temperature;
- Magnetic Effects;
- Magnetoelectric Media;
- Phonons;
- Pyroelectricity;
- X Ray Analysis;
- Solid-State Physics