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Though the anomalous antiferromagnetism of zinc ferrite was a subject of intensive studies in the past, the unusually high magnetization of coprecipitated zinc ferrite at low temperatures has drawn renewed interest among researchers. The local structures of zinc ferrites around Fe and Zn atoms are measured using extended x-ray-absorption fine structure and the results are discussed in correlation with their magnetic properties. The structure around the Zn atom was found to differ between zinc ferrite produced by ceramic and coprecipitation techniques. The position of the second-nearest neighbor of the Zn atom for coprecipitated zinc ferrite was shorter than the one produced by the ceramic method. This suggests the possible occupation of the Zn atoms in the octahedral sites and the cause for the unusually high magnetization in coprecipitated zinc ferrite. Furthermore, the intensity of the peak is weak compared to the one produced by the ceramic method. This is thought to be due to the deformation induced by the occupation of zinc ions in the octahedral sites, causing a decrease in the structural periodicity.

Yttrium aluminum garnet (YAG) precursors for transparent ceramics were synthesized by the urea method under various [urea]/[metal ions] ([U]/[M]) conditions. Monophase YAG was obtained from solutions with a high [U]/[M] ratio after calcination at a temperature of 1200°C.The condition of the precipitates seemed to indicate that the yttrium compounds had precipitated onto the aluminum compounds. The surface morphology and size of the particles were controlled by the [U]/[M] ratio. The different reaction sequences of YAG crystallization for low-and high-ratio samples were dependent on morphology, size, and the quantity of chemical species that was precipitated as carbonate and/or sulfate compounds.

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Nanostructured CdFe2O4 spinel powders with various grain sizes ranging from 60 to 4 nm were synthesized by ball milling the bulk material. The magnetization measurements at 1 and 9 T reveal a spin-glass-like surface structure and the material is found to have a large anisotropy. Mössbauer studies at 10 K in external magnetic fields of 6 and 8.5 T applied parallel to the direction of gamma rays could clearly show that CdFe2O4 behaves like a mixed spinel on reducing the grain size to nanometer level and exhibits ferrimagnetic ordering. Fe3+ spins at both A and B sites exhibit spin canting.