Particle interaction in polydisperse magnetic fluids: Experimental aspects of small-angle neutron scattering applications

The paper considers the experimental aspects of the observation of interaction effects in magnetic fluids with size polydisperse nanoparticles by means of small-angle neutron scattering (SANS). The possibilities of the method are discussed for different regimes of interaction predicted by the theory of dipolar fluids. The typical effects related to the experimentally observed structure-factor under different conditions, as well as possible ways of its theoretical description are analyzed.