A new tomographic technique, based on synchrotron X-ray diffraction, has been used to chart polymorphic content and crystallite alignment inside a model pharmaceutical reactor. This reveals complex behavior according to crystallite shape/size characteristics; in particular, stirring induces pronounced crystal zonation marked by a boundary “alignment band” in which the crystallites adopt a “stand on edge” orientation.

Variations in the composition and microstructure of Mn-Zn soft ferrites have been directly correlated with spatial variations in electrical resistivity, which were both observed to occur on a length scale of approximately 500 μm. Tomographic energy dispersive diffraction imaging (TEDDI) was used to determine the nonsystematic change in the lattice parameter across the sample volume (8.48±0.05 Å) at a spatial resolution of 50 μm. We have used a microprobe contact technique to measure the local electrical resistivity (∼35 Ω cm) and density functional theory to model the band structure. The band structure calculations directly utilized the experimentally measured lattice parameters from the TEDDI measurements and were in good agreement with the measured resistivity. The mean band gap shrinkage was found to be 0.02 eV. This value for Eg was found to account well for the observed 10−20 Ω cm resistivity variations.

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