X-ray fine structure study and bonding in some ferrites

Extended X-ray absorption fine structure (EXAFS) of the iron K edges in copper, cobalt, zinc and manganese ferrites is studied and the EXAFS parameter α of the Lytle, Sayers and Stern's theory is shown to be a measure of fractional covalency. The linear relationship between metal to oxygen (iron to oxygen) distance and the parameter α leads us to conclude that the copper ferrite is the most covalent among the four ferrites studied in the present investigation.