Scattering from all the k=0 first-order Raman-active phonons in FeBO3 and FeF3 has been observed. Underlying the A1g phonon in FeBO3 is a broad second-order phonon-scattering peak which accounts for the peculiar temperature behavior of the A1g band when viewed with low resolution. Scattering from magnon-pair states has been observed at 538 cm-1 in FeBO3 and at 564 cm-1 in FeF3. The nearest-neighbor-exchange parameters J are 19.2 and 20.1 cm-1, respectively. Estimates are given for various processes by which exchange striction may contribute to first-order phonon scattering. There are no observable effects due to a strong magnon-phonon interaction as previously reported for FeBO3.
ASJC Scopus subject areas
- Condensed Matter Physics