Abstract
The ferromagnetic structure of has been determined from powder neutron-diffraction data collected at 20 K on a sample synthesized at high pressures using a cubic anvil press. is a distorted perovskite that crystallizes in the monoclinic space group with unit-cell parameters and reduced Data analysis reveals a collinear ferromagnetic structure with the spin direction along [010] and a magnetic moment of There is no crystallographic phase transition on cooling the polar room-temperature structure to 20 K, lending support to the belief that ferromagnetism and ferroelectricity coexist in Careful examination of the six unique Mn-O-Mn superexchange pathways between the three crystallographically independent sites shows that four are ferromagnetic and two are antiferromagnetic, thereby confirming that the ferromagnetism of stems directly from orbital ordering.
- Received 28 March 2002
DOI:https://doi.org/10.1103/PhysRevB.66.064425
©2002 American Physical Society