The 57Fe magnetic hyperfine field in Au-Fe alloys (evidence favoring the two Fe environment model of Au-Fe alloys)

The Moessbauer magnetic hyperfine spectra (mhs) of quenched Au-Fe alloys at 4.2 K for various Fe concentrations have been known for some time. The interpretation of the concentrated alloy spectra has been an unresolved question for two decades. The interpretation of these spectra has followed two dissimilar approaches. The first assumes the spectra to be a superposition of two mhs. This implies that there are predominantly two Fe environments in these alloys. The second assumes the spectra to be a superposition of many mhs, each being weighted on the basis of an assumed random distribution of Fe atoms. The purpose of the present investigation is to generate evidence that either does or does not favor the two Fe-environment hypothesis. The authors report the results of a critical analysis of the variation of the magnetic hyperfine field with Fe concentration. This turns out to yield evidence in favor of a two Fe-environment model of these alloys. (Auth.)