This multidisciplinary project in the area of materials chemistry is jointly supported by the Inorganic, Bioinorganic and Organometallic Chemistry Program and the Solid State Physics Program. The collaborating investigators are Dr. Christopher M. Sorensen and Dr. Kenneth J. Klabunde of Kansas State University and Dr. George C. Hadjipanayis of the University of Delaware. Research will continue on the synthesis and evaluation of ultrafine magnetic particles, with the goals of learning more about the fundamental properties of these particles compared to bulk samples, to develop convenient methods for synthesis, protection and control of particle sizes and microstructure, and to gain a better understanding of the chemistry and physics of the processes by which they are formed. A broad range of synthetic approaches to the preparation of metallic, metal boride and metal oxide particles in the size range of 1-1000 nm will be investigated. Synthetic techniques will include metal atom clustering in cold matrices under inert gases and sputtering. Also to be investigated are reduction of metal ions by borohydride, hydroxide precipitation and digestion, and pyrolysis of aerosols. Reversed micelle techniques will be explored for the control of particle sizes, and the trapping of small particles in structural media, such as polymers, zeolites or vycor glass, will be investigated also. Magnetic particles will be thoroughly characterized with respect to chemical composition, morphology, magnetic ordering, magnetic moment, coercivity, and phase transformations.