Electronic structure of FeNi alloys studied by means of X‐ray photoelectron spectroscopy. I. Valence bands

Abstract

Abstract XPS spectra of FeNi alloys are measured. Using the spectroscopic, thermodynamic, and magnetic moment data so far available a consistent model of density of states for the FeNi alloys is proposed. This model is based on the band theory of ferromagnetism and some known properties of the electronic band structure of the first series transition metals. The measured XPS valence band spectra can be explained by means of the model DOS neglecting the influence of the transition probabilities. The CPA calculations so far available for FeNi do not fit the spectra satisfactorily. The model assumes the d‐bands to penetrate each other. The up‐spin bands are shifted against the down‐spin bands by a rigid exchange splitting corresponding to the measured atomic magneton number in the alloy. The model neglects the spin–orbit coupling which would couple states of opposite spin but this influence should be small.