Magnetic Behavior and Structure of Nanoparticulate ZnFe2O4 and MgFe2O4 by Magnetometry and Neutron Diffuse Scattering

Two series of nanostructured ZnFe2O4 and MgFe2O4 samples, each of which consists of four nominally identical samples of different nanoparticulate sizes (average), Φ ~ 90 nm, Φ ~ 21 nm, Φ ~ 15 nm, and Φ ~ 9 nm, were synthesized by the mechanochemical route. The thermal- and inversion-parameter-dependent magnetic order and transformation of magnetic ordering for these two series were studied through magnetization experiments over the temperature range from 2 K to 350. For the various nanoparticulate ZnFe2O4 samples varied from Φ ~ 90 nm to Φ ~ 9 nm, the correlation among three different magnetic orders; antiferromagnetic long-range order, ferromagnetic long-range order, and antiferromagnetic short-range order, was explored by polarization analysis of the consequent neutron diffuse scattering over the temperature range from 1.5 K to 295 K...