Combinatorial and topological modeling of cluster self-assembly of the crystal structure of zeolites

Combinatorial and topological modeling of packings of symmetrically connected polyhedral T12 clusters (hexagonal prisms), which are most widespread in crystal structures of zeolites, has been performed. Packings of T12 clusters are periodic 1D chains (11 types) and 2D microlayers (15 types). 2D microlayers that can be involved in the self-assembly of 3D zeolite structures described by tetracoordinated T nets are selected. Computer methods (the ToposPro program package) have been used to establish a correspondence with zeolites CHA (Chabazite, Ca6(H2O)40Al12Si24O72), AEI (AlPO-18, Al24P24O96), SAV ((C18H42N6)2(H2O)7Mg5Al19P24O96), KFI (Na30(H2O)98Al30Si66O192), GME (Gmelinite, (Ca,Na)4(H2O)24Al8Si16O48), AFX (SAPO-56, H3Al23Si5P20O96), and AFT (AlPO-52, Al36P36O144) for 7 out of 11 obtained models of 3D frameworks. Modeling of 3D polytypes of the GME (1L type)–AFX (2L type)–AFT (3L type) family has resulted in a new 3L polytype with the following crystallographic parameters: a =13.75 Å, c = 30.00 Å, V = 4912.0 Å3, sp. gr. P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\bar 6$$\end{document}m2 (no. 187). It is established that the 2D self-assembly of known zeolite structures is accompanied by pairwise binding of all (T12 + T12) clusters with the formation of 4Т rings, and the number of bonds between complementary chains during the formation of microlayers is maximum. Three types of obtained frameworks, which have no analogs among zeolites, exhibit low chain connectivity during microlayer formation in all cases.