Magnetic behavior ofCr74Fe26alloy investigated by Mössbauer spectroscopy

Two recently published comments [P. A. Beck, Phys. Rev. B 39, 752 (1989) and D. Boumazouza et al., Phys. Rev. B 39, 749 (1989)] have drawn attention to the interesting magnetic behavior of reentrant spin-glass systems. We present a temperature-dependent Mössbauer-effect study on ${\mathrm{Cr}}_{74}$ ${\mathrm{Fe}}_{26}$ alloy whose composition is close to and slightly above the percolation threshold (${\mathit{x}}_{\mathrm{Fe}}$=19.9 at. %), to resolve the controversy that has arisen out of these discussions. Our results suggest that the nature of magnetic ordering at the paramagnetic-to-ferromagnetic transition in this system also does not correspond to a true cooperative transition, as pointed out by Beck for ${\mathrm{Au}}_{82.5}$ ${\mathrm{Fe}}_{17.5}$ alloy.