The magnetic properties of the MgCd ferrite system by Mössbauer spectroscopy

The Mg-Cd ferrite system has been studied in detail by means of Mössbauer effect at 80K. Mössbauer spectra for x = 0.0 to 0.6 suggest the existance of two hyperfine fields, one due to the Fe³⁺ octahedral ions (B-sites) and the other due to the Fe³⁺ tetrahedral ions (A-sites), while for x = 0.8 it shows relaxation behaviour and for x ≥ 0.9 it exhibits a paramagnetic quadrupole doublet. The variation of nuclear magnetic fields at the A and B sites are explained on the basis of supertransferred hyperfine interactions. It has been found that the QS increases from MgFe₂O₄ to CdFe₂O₄ as the cadmium concentration is increased.