Crystalline Fe25Zn75 powder alloys (Gamma(1) phase) have been prepared
by mechanical alloying of pure elemental powders. A crystalline Fe27.
9Zn72.1 alloy (Gamma phase) was obtained after adequate annealing. The
Mossbauer spectra at room temperature displayed three doublets before
annealing, corresponding to iron atoms located at the outer tetrahedr
al, inner tetrahedral and octahedral sites in the unit cell of Fe25Zn7
5. For the annealed sample, two doublets associated with iron atoms lo
cated at two tetrahedral inequivalent sites in the unit cell of Fe27.9
Zn72.1 were observed. This Gamma(1)-to-Gamma-phase transition was conf
irmed by X-ray diffraction and Mossbauer spectroscopy measurements.