Hello
As you know inversion degree plays an important role in magnetic properties of spinel nanoferrite. I synthesize Ni.Co.Fe2O4 ferrite nanoparticles. So I want to know how inversion degree can affect on magnetic property in spinel nanoferrite (in this case Ni.Co.Fe2O4 ferrite nanoparticles)??
Just to add: it is usually rather difficult to measure the actual inversion degree of any spinel oxide. You should do some Mossbauer spectrometry; neutron diffraction, magnetization measurements or X-Ray Spectrophotometry (XPS). Preferably all af them!
Hope this helps.
The net magnetization in spinells according to Néel model is just the difference in moment in the 2 sites A and B. Therefore the concentraion of magnetic ions in the 2 sites determine the net magnetization. Sonce Co, Ni nd Fe2+ , Fe3+ all have different magnetic moment, any change in the relative concenration leads to ta change in the net magnetization. Now to determin the exact concentration of each is a bit involved and even difficult if you have more than 2 different magnetic ions. Möss bauer will tell you the concentration of Fe ions but not about Co or Ni.
We can only calculate the net magnetization of a ferrimagnetic material (not only spinel ferrites) at 0 K. According to the rules of Anderson the kind of the superexchange interaction between two magnetic cations (M) depends on the geometry of the M-O-M configuration via the oxygen anion O. In an 180 degrees M-O-M configuration the magnetic moments of the two cations align themself antiparallel wheras in an 90 degrees configuration parallel. These simple rules allow us to determine the magnetic moments "lattice" and calculate its net magnetizarion at 0 K. The magnetic moment of a single cation is calculated using the Hund's ruels. The inversion factor affect the M-O-M configuration, consequently the net magnetization.
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