The Mo¨ssbauer effect has been used to study the microscopic magnetic properties of the cubic microwave ferrite (Zn0.41Ni0.59)Fe2O4at 300 K. The magnetically split spectrum is broad and unresolved due to the overlap of the hyperfine magnetic fields at the tetrahedral and octahedral sites. This is caused by a distribution of magnetic fields at each site. The distribution is especially large and asymmetric at the octahedral site and is due to the fact that the iron atoms at this site are influenced by the presence of both iron and zinc at the tetrahedral site. The octahedral site is more sensitive to changes in the number of zinc neighbors than is the tetrahedral site. Assuming a random distribution of the zinc at the tetrahedral site, and knowing the fraction of zinc in the ferrite, the binomial distribution has been used to calculate the expected magnetic‐field distribution at the octahedral site as a function of the number of zinc neighbors. These figures have been compared with the magnetic‐field distribution profile determined from the fit to the Mo¨ssbauer spectrum. Sufficiently good agreement has been found to allow us to isolate the magnetic‐field contribution due to most of the different numbers, between zero and six, of neighboring zinc atoms.
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