Sala Constitucional, social permanente.

A cheap, simple procedure has been developed here capable of producing fine nanopowders with tunable magnetizations from 30-50 emu/g at 10000 G by adjusting the Co2+/Fe2+ ratio in ferrite compounds. Manipulating this ratio also allows control of the degree and orientation of Faraday by a sample. Applying the information gathered from the techniques employed, the target product has been formed, but with its structure dependent on this ratio. We have observed a tendency for cobalt to migrate to the octahedral positions at higher ratios and occupy both sites at lower ones which has resulted in the identification of an ISCT between cobalt ions around 550 nm. This migration to the octahedral site is effectively a high-spin, low-spin crossover by divalent cobalt cations as a function of concentration. Magnetic and magnetic-optical measurements have been used in this study to gather essential information concerning the spatial orientations of cations in this compound; a structural parameter that is difficult to obtain by other methods.

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VITA

Byron L. Scott was born May 28, 1980 in Cullman, AL and relocated to Pascagoula, MS later that year. He enrolled in the University of New Orleans in fall 2000 where he received his B. S. in Chemistry in May 2003. He will receive his M. S. in Applied Physics from the University of New Orleans in December 2007.