Evidence of clustering in Heusler like ferromagnetic alloys

Two Heusler like alloys Fe2CrAl, and Mn2CoSn had been prepared and studied using the Mossbauer effect. Both these alloys were ferromagnetic in nature. Their Mossbauer spectra showed the co-existence of a paramagnetic portion along with magnetic hyperfine part upto temperatures well below their Curie temperatures. Low temperature Mossbauer spectra for both these alloys showed a steady variation in the intensity of the paramagnetic portion. X-ray diffraction studies made on these samples ruled out the possibilities of a separate phase. Explanation of the observed phenomena is given by clustering around the magnetic ions present in these samples.