Magnetic properties of Er2Fe14−xMnxC

The magnetic properties of the compounds Er2Fe14−xMnx have been determined by means of X-ray diffraction, magnetic measurement and 57Fe Mössbauer spectroscopy. Magnetization measurements made in fields up to 38 T showed that the saturation moment exhibits a minimum at a Mn concentration corresponding to about x=2, due to the antiparallel coupling between the R and 3d sublattice magnetizations the latter becoming strongly reduced with increasing Mn concentration. The reduction of the 3d-sublattice magnetization is accompnied by a corresponding reduction in the 57FE hyperfine fields and by a lowering of the Curie temperature and the spin orientation temperature. Most of the compounds investigated have a break in the magnetization curves measured at 4.2 K which is interpreted as the onset of decoupling between the antiparallel rare earth and 3d sublattices. A mean field analysis was used to derive the intersublattice molecular field coefficient nRT.