Indication of an electron redistribution in the d band of Fe alloyed with Si

Abstract

Two alloys of the Fe-Si system have been investigated by means of polarised neutron diffraction: a 7.5 at.% Si alloy and a 14.3 at.% Si alloy. The alloy of higher Si content showed some long-range order. For Fe₉₂₅Si₇₅ both the spherical and aspherical form factors were found to be equal within errors to those of pure Fe; for Fe₈₅₇Si₁₄₃ the magnetic moments and form factors were obtained for the three different sites. The Si site was found to have a form factor very different from that of pure Fe. The authors discuss these results and show that they are probably due to the contribution of the electrons at the bottom of 3d band states of Fe atoms when they occupy the Si site.