Mossbauer and Ac-susceptibility measurementshave been carriedout on the alloy series FeAl,_,Mn, within the range 0.05 S x b 0.40. M6ssbauer spectra reveal the presence of electron charge density and magnetic hypefine field (BM) distributions at two iron sites. Thecharge density rises linearly with Mn concentration while B,,increases non-linearly with x indicating a polarized spin density of the itinerant electrons at the Fe nucleus due to the near neighbouring Fe and Mn magnetic moments. The onset of magnetism is explained by the formation of magnetic moment at the iron atom when AI atoms are removed and by the nearest neighbouring iron clustering. Magnetic measurements indicate the presence of mictomagneticclusters and show a transition from paramagneticstate tomagneticglass state for all the alloys. NO onset of ferromagnetism with increasing x was observed even at the concentration x = 0.4, in contrast to that observed in FeAI, $U, at a lower concentration x = 0.325. Comparison of the transition temperatures obtained from Mossbauer and ACsusceptibility measurements indicate relaxations of the magnetic clusters.

Magnetic susceptibility and Mossbauer spectroscopy studies were carried out on the alloy series FeAl1-xCux (0

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