A Mossbauer study of CoMo-substituted barium ferrite

Well-resolved Mossbauer spectra were obtained for CoMo-doped barium ferrite with variable doping (0-33% Fe), heat-treatment temperature (825-1200 degrees C), and sample temperature (90-300 K). Substitution was observed to occur primarily on the 12-K site, with little or no lattice distortion. A fitting model using five independent components, each a sextet, yielded the magnetic hyperfine field (ionic moment) of each site as a function of doping and sample temperature. A 10% reduction of the moment on the 2a site was observed upon doping, which results from its proximity to the 12-K site. Other sextet parameters were generally constant or followed monotonic trends.>