Structure and magnetic properties of nanocrystalline ferrimagnetic CdFe2O4 spinel

The nanocrystalline CdFe2O4 with various grain sizes were synthesized by ball milling in bulk material. The magnetization measurements reveal a spin-glass like surface structure and the material is found to have a large anisotropy. Mossbauer effect experiment at 10 K in an external magnetic field of 6 T applied parallel to the direction of gamma rays could clearly show that CdFe2O4 behaves like a mixed spinel on reducing the grain size to a few nanometers and that it exhibits ferrimagnetic ordering. Fe3+ spins at both the sites exhibit spin canting. The cation inversion is found to increase with decrease in grain size.