Magnetic properties of Ho2Fe17-xMnx - influence of Mn substitution

The structural and magnetic properties of Ho2Fe17-xMnx (x=0-5) have been investigated by x-ray diffraction, Mossbauer spectroscopy and DC magnetization measurements (0-5 T) over the temperature range 4.5-350 K. Similar to other ferrimagnetic R2Fe17-xMnx systems, the unit cell volume generally increases with Mn content other than for low Mn values where a slight maximum is detected around x similar to 0.5. The nature of the magnetic phase transitions around T-C is shown by Arrot plot analysis to be second order for all samples. The Curie temperature remains essentially unchanged for Mn contents up to x=1.0 (T-C=336 K for x=0.0, T-C=338 K for x=1.0) before decreasing steadily with further increase in Mn content (T-C=209 K for x=5). The Fe-57 hyperfine interaction parameters have been determined from variable temperature Mossbauer spectra.