The Synthesis and Structure of SSZ-73: an All-Silica Zeolite with an Unusual Framework Topology
The Synthesis and Structure of SSZ-73: an All-Silica Zeolite with an Unusual Framework Topology
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DOI：
10.1021/cm0705284
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发表时间：
2007-07
影响因子：
8.6
通讯作者：
D. Wragg;R. Morris;A. Burton;S. Zones;K. Ong;Greg S. Lee
中科院分区：
文献类型：
--
作者：
D. Wragg;R. Morris;A. Burton;S. Zones;K. Ong;Greg S. Lee
本文报道了新型全硅沸石SSZ-73的合成、表征和晶体学研究。SSZ-73的骨架拓扑结构与磷酸铝STA-6（SAS）是同构的。SSZ-73是使用3-乙基-1，3，8，8-四甲基-3-氮鎓双环[3.2.1]辛烷阳离子作为结构导向剂从含氟凝胶制备的。SSZ-73是具有八环孔的一维系统的全硅沸石。然而，SSZ-73由于结构中相当大的笼而具有非常高的可膨胀体积（0.25cm3/g）。单晶X-射线衍射研究表明，氟驻留在双六环笼的SAS框架。对SAS、RTH、ITE和STF的全硅框架中结构导向剂的两种几何异构体进行了分子对接研究。研究结果表明，桥头碳原子上带有顺式乙基的异构体可能是SSZ-73的结构导向剂，SSZ-73的结构导向剂可能是一种新的结构导向剂。
This paper reports the synthesis, characterization, and crystallographic studies of the new all-silica zeolite SSZ-73. The framework topology of SSZ-73 is isostructural with the aluminophosphate STA-6 (SAS). SSZ-73 is prepared from fluoride-containing gels using 3-ethyl-1,3,8,8-tetramethyl-3-azoniabicyclo[3.2.1]octane cation as a structure-directing agent. SSZ-73 is an all-silica zeolite with a one-dimensional system of eight-ring pores. However, SSZ-73 possesses a remarkably high micropore volume (0.25 cm3/g) due to the rather large cages in the structure. A single-crystal X-ray diffraction study of the as-made material shows that fluoride resides within the double six-ring cages of the SAS framework. Molecular docking studies were performed for the two geometric isomers of the structure-directing agent in the all-silica frameworks of SAS, RTH, ITE, and STF. The studies suggest that the isomer with the ethyl group cis to the bridgehead carbon is the likely structure-directing agent for SSZ-73 and that th...