The Zeolite Conundrum: Why Are There so Many Hypothetical Zeolites and so Few Observed? A Possible Answer from the Zeolite-Type Frameworks Perceived As Packings of Tiles

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• 作者：Vladislav A. Blatov ; Gregory D. Ilyushin ; Davide M. Proserpio
• 刊名：Chemistry of Materials
• 出版年：2013
• 出版时间：February 12, 2013
• 年：2013
• 卷：25
• 期：3
• 页码：412-424
• 全文大小：807K
• 年卷期：v.25,no.3(February 12, 2013)
• ISSN：1520-5002

文摘

In the attempt to explain why there are so many hypothetical zeolites and so few observed, a model of assembling zeolite-type frameworks as a packing of natural building units (smallest cages) and/or essential rings (smallest windows) is proposed. The packing units have no common T atoms, hence the model takes into account the process of polycondensation of T⁴⁺(OH)₄ or [T³⁺(OH)₄]鈭?/sup> complex groups resulting in oligomeric T_nO_m(OH)_k units, eliminating water molecules, and forming T鈥揙鈥?i>T bridges. The packings were modeled for all zeolite minerals and most of the synthetic zeolite-type frameworks accounting for 163 zeolites of the 201 known. It is shown that the extra-framework cations can play a role of templates for the packing units. Application of the model to 1220 hypothetical zeolites shows that only a small set could be explained as packing of tiles, suggesting a possible ranking of feasibility that may help to unravel the zeolite conundrum.

Keywords:

zeolites; hypothetical zeolites; self-assembly; computation methods; tilings