MAGNETIC STRUCTURE AND MAGNETIC PROPERTIES OF Y 3 Fe 5-x Mn x O 12

Neutron diffraction patterns have been obtained for polycrystalline Y 3 Fe 5-x Mn x O 12 at 300 K. The fraction of octahedral sites occupied by Mn 3+ has been found to be 0.72 for x=0.05 and 1 for x=0.09. The magnetic moments of tetrahedral sites and octahedral sites have been determined respectively for x=0.05 and 0.09. The observed magnetic scattering is consistent with the Neel model and the measured saturation moment.Magnetizations were measured as a function of applied magnetic field from 800 Oe to 10 kOe in the range of 1.5-300 K. Magnetic anisotropy were determined from the approach to saturation, |k 1 | was found to decrease with Mn 3+ content.