Abstract
We report the preparation and investigation of untwinned single-crystal specimens of . They were grown from a flux without oxygen annealing treatment, show a of 89 K, a transition width of K, and an almost complete magnetic shielding effect. The Raman scattering reflects the orthorhombic symmetry and untwinned structure of the crystals. Furthermore, we found in this crystal that the softening of the Raman mode at 335 through occurs within a temperature region 10 times narrower than previously reported.
- Received 24 February 1988
DOI:https://doi.org/10.1103/PhysRevB.37.9860
©1988 American Physical Society