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Structure studies were performed on nanocrystalline powder of MgO xerogel prepared by the sol-gel technique, producing high purity, chemically homogeneous materials of relatively high specific surface area. Magnesium methoxide was used as an MgO precursor. The wet gel was dried under conventional conditions, yielding xerogel with periclase phase; the only crystalline form of magnesium oxide. The X-ray diffraction, scanning and transmission electron microcopies were used as the tools of structure analysis. The Toraya PRO-FIT procedure and the Rietveld refinement method were applied for X-ray data analysis. Both techniques apply the Pearson VII function for the description of line profiles. The …

Materials with MgO nanocrystallites were prepared by sol-gel synthesis. Alcogels were dried either supercritically at 538 K or in supercritical CO2. Conventional drying was also applied. Structure studies were performed by X-ray diffraction, scanning and transmission electron microcopies. Nitrogen adsorption/desorption measurements were also performed. Calcination of dry gels at 723 K under vacuum yielded MgO nanocrystallites. In the studied materials the presence of the amorphous phase was observed. It is also stated that MgO nanocrystallites are immersed in an amorphous matrix. Morphology of supercritically dried samples is similar; rough surface of powder particles is observed. Powder particles of conventionally dried …