Determining the Magnetic Structure of Ferrite Nanoparticles

Science Center, Bent Corridor

Magnetic nanoparticles have a variety of uses in biomedical and technological applications including hyperthermia, ultra-dense data storage, and water decontamination. We are developing and implementing an assortment of methods to help in determining and controlling the magnetic structure of ferrite nanoparticles; here we are describing our progress on a number of projects. A close packed structure modeling program is being developed to help explain interesting features in the small angle neutron scattering of manganese ferrite based particles. In another project, we are utilizing the low moment side of an unusual array of magnets to separate Fe3O4 particles based on small differences in the magnetic moment. Last, we have taken small angle x-ray scattering data to help characterize the structural features of Fe3O4 nanocubes in contrast to typical nanospheres. Preliminary versions of the model indicate that large increases in domain size may help explain the data at high fields and low temperatures. In separations so far, the median moments of separated samples correlate with anticipated trends. X-ray scattering data for the nanocubes are suggestive of simple cubic packing.