| Abstract
| - While extensive commercial success has been achieved through the use of organic molecules in thesynthesis of aluminosilicate zeolites, the synthesis of the germanium-based zeolite structures using organicstructure-directing agents is a largely unexplored area. Here we report a novel class of germanate zeolitestructures prepared with inorganic cations or organic amines as structure-directing agents. These new materialspossess five 4-connected 3-dimensional topologies with large (12-ring), medium (10-ring), small (8-ring), orultrasmall (6-ring) pores. They have a variety of chemical compositions such as various Ge to Ga (or Al)ratios and exhibit interesting structural features such as helical chains and odd-membered rings. UCSB-15GaGeand UCSB-15AlGe are the first germanate-based structures with 5-rings. UCSB-7 refers to a collection ofisostructural, large-pore zeolite-like structures constructed by the cross-linking of helical ribbons. UCSB-3GaGe is the only known T3+/T4+ (T refers to tetrahedral atoms) based zeolite structure with the net 38 topology.This structure is unusual because of its very high framework charge density unsurpassed by other amine-directed zeolite structures. GaGe-SOD2 and AlGe-SOD2 (sodalite analogues) have an unusually low frameworksymmetry for a sodalite structure. The cubic GaGe-SOD1 (or AlGe-SOD1) and the triclinic GaGe-SOD2 (orAlGe-SOD2) are ideal examples of the compositional and structural control of the inorganic framework bystructure-directing amines. GaGe-ANA1 and GaGe-ANA2, two gallogermanate analcime analogues, arenoncentrosymmetric, unlike many other analcime structures.
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