Study of quadrupole interaction in ferrite spinel CdFe2O4

The quadrupole interaction in the ferrite spinel CdFe2O4 was studied above the Neel temperature (< 20deg K) both at Fe and Cd sites using Moessbauer effect and Time Differential Perturbed Angular Correlation (TDPAC) technique. The ferrite spinel was prepared by mixing stoichiometric amounts of Fe2O3 and CdO and sintering at 800deg C for two days after thorough mixing. Moessbauer spectroscopic and X-ray diffraction studies confirmed single phase formation of the spinel. TDPAC measurements were done using radioactive 111In which had been diffused and was expected to occupy the site A in the lattice. An unexpectedly high electric field gradient was observed. Possible reasons are discussed. (M.G.B.)