Neutron diffraction studies of magnetic moments in dilute transition metal alloys

Measurements of the magnetic disorder scattering of neutrons from dilute ferromagnetic alloys allow the spatial distribution of the magnetic moment disturbance around the solute atoms to be investigated. Results are presented for dilute polycrystalline iron based alloys showing the magnetic moment distribution around manganese, chromium and vanadium atoms. The scattering from manganese impurities indicates that their presence has no appreciable effect on the moment of nearby iron atoms. In the case of chromium and vanadium impurities, the data can only be interpreted in terms of a small increase of moment on iron atoms which are roughly 4 A distant from solute atoms. There appears to be a negative moment on the impurity atoms themselves.