Low Temperature Transitional Aluminas: Structure Specifics and Related X-ray Diffraction Features

Despite the fact that metastable aluminum oxides are actively used in industry, there is a discrepancy in the literature regarding their crystal structure. All this leads to difficulties in data interpretation and, as a consequence, classification problems. This work is aimed at solving these tasks. The main features of powder X-ray diffraction of typical samples of three Al2O3 polymorphs (γ-, χ-, η-) are analyzed. Specifics and fundamental differences in X-ray scattering and their relationship with the structural organization at the nanostructure level are clearly shown. The work demonstrates the possibilities of analyzing experimental powder X-ray diffraction data using a modern approach based on the Debye Scattering Equation for studying the organization of such complex systems.