A Most Unusual Zeolite Templating: Cage to Cage Connection of One Guest Molecule

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• 作者：S. I. Zones ; Son-Jong Hwang ; Marilyn M. Olmstead ; Simon J. Teat ; Anna Jackowski ; Allen W. Burton ; Chul Kim
• 刊名：Journal of Physical Chemistry C
• 出版年：2010
• 出版时间：May 20, 2010
• 年：2010
• 卷：114
• 期：19
• 页码：8899-8904
• 全文大小：267K
• 年卷期：v.114,no.19(May 20, 2010)
• ISSN：1932-7455

文摘

An unusual case of a diquaternary ammonium dication, with large bulky end groups built from the tropane moiety and connected by a C4 methylene chain, is found to reside in zeolite SSZ-35 (STF). The structure of the guest/host product is such that the tropane bicylic entities reside in the shallow cavities of the cages of the STF structure and the C4 methylene chain runs through the 10-ring (5.5 Å) window that connects the cages. This is a most unusual (and energy-intensive) templating of a zeolite structure with the guest molecule spanning two unit cells. The unusual result was found by single crystal studies with the addition of the use of the SQUEEZE program to show a consistent fit for the guest molecule following from measured electron densities in the crystal structure work. These analyses were followed with MAS NMR studies to confirm the integrity of the diquaternary guest molecule in the host sieve. A few comparative diquaternary guest molecules in MFI zeolite are also studied.