Abstract
The discovery of high-temperature superconductivity in doped copper oxides, which in their insulating forms are nearly ideal two-dimensional spin-1/2 Heisenberg antiferromagnets, has stimulated great interest in finding additional examples of such magnetic systems. We find that , which has the structure and should have a 5 low-spin (S=1/2) electronic configuration, develops a ferromagnetic moment near 250 K. The small size of the remanent moment (), and our structural studies, however, imply that this is weak ferromagnetism which appears at the Néel temperature due to a Dzyaloshinsky-Moriya interaction, in a manner analogous to that seen in .
- Received 11 October 1993
DOI:https://doi.org/10.1103/PhysRevB.49.9198
©1994 American Physical Society