抄録
The surface magnetization of Ni fine particles has been measured by the small angle scattering of polarized neutrons. It is pointed out that the θ dependence of the flipping ratio R(θ) scattered at small angles θ is very sensitive to the existence of anomalous magnetic surface layers but insensitive to the existence of particle-particle spacial correlations. Beside these, the scattering cross section is extremely high, encouraging us to study the surface state by neutron scattering. Based on the informations of the radius of Ni and the thickness of the NiO coverage obtained from X-ray diffraction, a model is proposed so as to get a best fit to the observed R(θ). According to this model, there exists about 3∼4 magnetic dead layers or 2 layers of reversed magnetization at the Ni surface.
