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The crystal structures of compounds with the general formula Cs{^[6]Al₂[^[4]<i>T</i>P₆O₂₀]} (where <i>T</i> = Al, B) display order-disorder (OD) character and can be described using the same OD groupoid family. Their structures are built up by two kinds of nonpolar layers, with the layer symmetries <i>Pc</i>(<i>n</i>)2 (<i>L</i>_2<i>n</i>+1-type) and <i>Pc</i>(<i>a</i>)<i>m</i> (<i>L</i>_2<i>n</i>-type) (category IV). Layers of both types (<i>L</i>_2<i>n</i> and <i>L</i>_2<i>n</i>+1) alternate along the <b>b</b> direction and have common translation vectors <b>a</b> and <b>c</b> (<i>a</i> ~ 10.0 Å, <i>c</i> ~ 12.0 Å). All ordered polytypes as well as disordered structures can be obtained using the following partial symmetry operators that may be active in the <i>L</i>_2<i>n</i> type layer: the 2₁ screw axis parallel to <b>c</b> [– – 2₁] or inversion centers and the 2₁ screw axis parallel to <b>a</b> [2₁ – –]. Different sequences of operators active in the <i>L</i>_2<i>n</i> type layer ([– – 2₁] screw axes or inversion centers and [2₁ – –] screw axes) define the formation of multilayered structures with the increased <i>b</i> parameter, which are considered as non-MDO polytypes. The microporous heteropolyhedral <i>MT</i>-frameworks are suitable for the migration of small cations such as Li⁺, Na⁺ Ag⁺. Compounds with the general formula Rb{^[6]<i>M</i>³⁺[^[4]<i>T</i>³⁺P₆O₂₀]} (<i>M</i> = Al, Ga; <i>T</i> = Al, Ga) are based on heteropolyhedral <i>MT</i>-frameworks with the same stoichiometry as in Cs{^[6]Al₂[^[4]<i>T</i>P₆O₂₀]} (where <i>T</i> = Al, B). It was found that all the frameworks have common natural tilings, which indicate the close relationships of the two families of compounds. The conclusions are supported by the DFT calculation data.