Co\u3csup\u3e57\u3c/sup\u3e and Fe\u3csup\u3e57\u3c/sup\u3e mössbauer studies of the spinels FeCo\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e4\u3c/sub\u3e and Fe\u3csub\u3e0.5\u3c/sub\u3eCo\u3csub\u3e2.5\u3c/sub\u3eO\u3csub\u3e4\u3c/sub\u3e

Mössbauer source and absorber spectra of FeCo O and Fe Co O have been obtained between 82 and 523 K. Interpretation of the spectra allow the cation distributions of the compounds to be determined. FeCo O is Co Fe [Co Fe Co ]O and Fe Co O is Co [Fe Co ]O . Spinel tetrahedral site quadruple splitting is observed in both compounds. © 1978. 2 4 0.5 2.5 4 2 4 0.55 0.45 0.45 0.55 1.0 4 0.5 2.5 4 1 0.5 1.5 4 2+ 3+ 2+ 3+ 3+ 2+ 3+ 3