FEATURES OF THE REAL STRUCTURE OF PSEUDOBOEHMITES: VIOLATIONS OF THE STRUCTURE AND LAYER PACKING CAUSED BY CRYSTALLIZATION WATER
K. I. Shefer, S. V. Cherepanova, Г‰. M. Moroz, E. Y. Gerasimov, S. V. Tsybulya
Keywords: pseudoboehmite, aluminum hydroxide, structure, simulation of diffraction patterns
Pages: 137-147
Abstract
Rietveld structure refinement and simulation of the diffraction patterns of partially disordered materials are used to study the real structure of nanoscale pseudoboehmite samples obtained by different technologies. The effect of various violations in the structure of these nanomaterials on diffraction patterns is analyzed. The introduction of corrections for the Lorentz and polarization factors in the determination of the cell parameter b by the position of the 020 diffraction peak in the pattern is shown to be important. A model for the atomic structure of pseudoboehmite is proposed. The model involves additional water molecules as compared to the structure of boehmite. The water molecules in the interlayer space of the layered boehmite structure are found to violate its regularity, which results in a decrease in the size of crystallites.
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