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Synthetic and X-ray structural details, optical and vibrational spectroscopic, and thermal properties of the materials [(CH 3 ) 4 N] 2 M 2 Ge 4 S 10 (where M ) Cu, Ag), are described for the first time. Rietveld PXRD full-profile structure refinements of [(CH 3 ) 4 N] 2 M 2 Ge 4 S 10 reveal a novel open-framework architecture in which dimetal M 2 2+ and adamantanoid Ge 4 S 10 4building blocks are alternately substituted into the tetrahedral Zn 2+ and S 2sites of a zinc blende lattice, all linked together by [Ge(µ-S)] 2 M-M[(µ-S)Ge] 2 metal-metal bonded bridging units. The metal-metal distances in the S 2 M-MS 2 "twisted I" dihedral unit are 2.761 Å (Ag) and 2.409 Å (Cu). These internuclear separations are shorter than the bulk metals themselves (2.89 Å, Ag; 2.54 Å, Cu). This implies that the adamantanoid Ge 4 S 10 4--based open-framework structure is held together by d 10 -d 10 M + -M + metal-metal bonds. FT-Raman provides a direct probe of this interaction. Dimetal-framework breathing vibrational modes are observed around 38 cm -1 for M ) Ag and 55 cm -1 for M ) Cu. In situ VT-PXRD analysis demonstrates that [(CH 3 ) 4 N] 2 Ag 2 Ge 4 S 10 retains its structural integrity upon exposure to air after in vacuo heating above the [(CH 3 ) 4 N] + loss temperature. It seems likely that the disilver connection of adamantanoid Ge 4 S 10 4building blocks confers thermal stability upon the framework.

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Synthetic methods have been developed which yield large single crystals and highly crystalline phase-pure microporous layered SnS-n materials. This allows study of the structure-property-function relations of these materials. The tin sulfide layer of the SnS-1 structure type contains hexagonally shaped 24-atom rings which are constituted by six Sn 3 S 4 broken-cube cluster building units, linked together by double bridge Sn(m-S) 2 Sn sulfur bonds. The SnS-3 structure type contains elliptically shaped 32-atom rings which are also constructed from six Sn 3 S 4 broken-cube clusters. However, they are linked by double bridge Sn(m-S) 2 Sn sulfur bonds as well as tetrahedral edge-bridging Sn(m-S 2 SnS 2 )Sn spacer units. The SnS-1 structure type [A 2 Sn 3 S 7 ] was obtained in the presence of A+=Et 4 N+, DABCOH+ (protonated 1,8-diazabicyclooctane), and a mixed template system of NH 4 +/Et 4 N+, while the SnS-3 structure type [A 2 Sn 4 S 9] emerged in the presence of A+=Prn 4 N+ and Bun 4 N+. Various SnS-1 and SnS-3 structures are examined and compared in relation to the size/shape of constituent template cations. A particular kind of structure-directing function was observed, that is, larger template molecules create larger void spaces within and between the tin sulfide sheets. Unique framework flexibility was discovered for both structure types. In order to accommodate the size/shape changes of templates, the flexible porous tin() sulfide layers are able to undergo a certain degree of elastic deformation to alter the architecture of void spaces within and between the layers, rather than forming a completely new porous structure type. This is believed to be responsible for the relatively small number of structure types so far discovered for tin() sulfide-based microporous layered materials compared to the myriad of three-dimensional open-framework structure types found for the zeolites and aluminophosphates. The observed differences among the various SnS-1 or SnS-3 structures is significant and has resulted in distinct adsorption behavior towards guest molecules. The TPA-SnS-3 framework is also found to be pressure sensitive. This all bodes well for envisaged chemical sensor applications for this class of porous materials. rials, denoted R-SnS-n, where R represents the occluded

For over half a century, zeolites have played a major role in the development of modern processes in the chemical and petroleum industries. [1] Their unique combination of physical and chemical properties are ideal for catalysis and separations for a broad range of molecules. Recent advances in zeolite synthesis have centered on high silica zeolite systems or have employed exotic templates. [2] However, low Si/Al ratio zeolites are particularly attractive because they can offer high acid site density for catalytic applications and greater ion-exchange capacity and compositional diversity for separation processes. We report here our discovery of two new zeolite materials, UZM-4 and UZM-5, synthesized at low Si/ Al ratios (Si/Al < 10) by using combinations of two of the most common organic templating agents, the tetramethylammonium (TMA + ) and tetraethylammonium (TEA + ) ions. [3] UZM-4 is a large pore 12-ring zeolite with the BPH framework type [4, 5] and a sufficiently high Si/Al ratio (1.5-2.5) to enable thermal stability. UZM-5 has an unprecedented framework type that contains an 8-ring pore system similar