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Description
The present work investigates the crystallographic and magnetic properties of post-annealed magnesium ferrite (MgFe2O4) powder using neutron diffraction within a comprehensive temperature range (10 - 300 K). The obtained crystallite and domain size variations show a robust correlation with the magnetic properties. Further, the magnetic behaviour was investigated using zero-field cooling (ZFC) and field-cooling (FC) magnetization. Further, temperature variation of magnetic domain size (Dm) and crystallite size are thoroughly examined. The observed reduction in domain size as the temperature decreases is attributed to the increase in the coercive field (HC). The magnetic moments for MgFe2O4 nano powder estimated through the Rietveld refinement of neutron diffraction patterns are consistent with the magnetic moment calculated from M(H) loops. Further, Electron Spin Resonance (ESR) technique is employed to investigate the magnetic behaviour of MgFe2O4 over a temperature range of 90 K to 300 K, focusing on dipolar and super-exchange interactions. The ESR spectra linewidth (ΔH_PP) of MgFe2O4 increases from 1225 Oe to 1870 Oe as the temperature decreases from 300 K to 90 K, indicating the enhancement of dipole magnetic interactions.
