SINGLE-CRYSTAL STRUCTURAL STUDY OF A NATURAL (ZN, MN) FERRITE

The structure of a natural ferrite with chemical composition Zn0.75Mn0 .75Fe1.50O4 has been determined using X-ray single crystal diffraction techniques. Unlike ZnFe2O4 and MnFe2O4, this material is tetragonal w ith space group I4(1)/amd, a = 5.964(2) Angstrom, c = 8.449(3) Angstro m, V = 300.5(2) Angstrom(3), and Z = 4. The structure was solved using the Direct Methods facilities of SHELXS-86 and refined by least-squar es using SHELXL-93. The final disagreement factors were R(F) = 0.0170, wR(F-2)= 0.0440 and S = 1.398 for all 82 independent reflections merg ed from the 476 reflections measured.