This paper reports synchrotron X‐ray powder diffraction and high‐resolution electron microscopy studies of the structural arrangement in γ‐Fe2O3. Powder diffraction data as well as high‐resolution electron microscopy show that the basic structure of γ‐ferric oxide possesses cubic symmetry (space group P4332), whereas the ordered distribution of the cation vacancies on the octahedral positions results in the formation of the tetragonal superlattice (space group P41212). The character of the superstructure orientation with respect to the developed planes of the γ‐Fe2O3 microcrystals obtained by different preparative techniques is also discussed.

The model of structure and structural transformation of the mesostructured carbon material CMK-1 was established by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) investigations. The investigations showed that the enantiomeric carbon subframeworks formed within the pores of the MCM-48 mesoporous template used for the material synthesis displaced with respect to one another without significant distortions after the dissolution of the silica wall of the template. The model proposed agrees well with TEM images observed. The XRD structural modeling of CMK-1 done using the continuous density function technique allowed perfect fit of the calculated to the experimental powder diffraction pattern and provided geometric characteristics of the material texture. The structural characteristics obtained agreed fairly well with TEM analysis and with previously reported adsorption data.

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