An Investigation of Iron Chromium Tellurates by Iron-57, Tellurium-125 and Iodine-129 Mössbauer Spectroscopy

The57Fe Mössbauer spectra recorded at 4.2K from the trirutile-type iron chromium tellurates of composition Fe2−xCrxTeO6, where x=0–2, show that the angle θ, which describes the perpendicular orientation of the magnetic moment to the basal plane of the Fe2TeO6 unit cell, is not changed by the incorporation of chromium until x exceeds 1.2 At this critical limit θ begins to rapidly cant to smaller values until, at compositions approaching Cr2TeO6, it approaches a parallel orientation to the basal plane. The125Te and129I Mössbauer spectra recorded from the compound FeCrTeO6 at 77 and 4.2K are consistent with the presence of a supertransferred magnetic hyperfine field at the tellurium nucleus ofca. 76 kG.