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Acta Cryst. (2014). A70, C186
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Interlayer expansion using silylating agents to connect layer silicates to 3D framework structures has proofed to be a versatile synthesis route to new micro-porous frameworks (1). We show here that also Me-cations can be used as linker agents. An acidic Fe-chloride solution was used in a hydrothermal reaction to convert the hydrous layer silicate RUB-36 into an interlayer expanded zeolite, containing Fe at the linker site. Structure analysis of the new material Fe-COE-3, Si19.14Fe0.86O42, showed that the porous framework is stable after calcination and contains Fe on T-sites at the linker position which connects the two silicate layers. From chemical analysis it is confirmed that every other linker site is occupied by iron. The material crystallizes in space group Pm with a = 12.200(9) Å, b = 13.981(8) Å, c = 7.369(2) Å, ß = 106.9(1)0. Fig. 1 shows the results of the final Rietveld analysis (chi2 = 8.8) and a projection of the framework structure along [001]. Because of the limited crystallinity of the material also the quality of the structure refinement is constricted. However, including complementary information from adsorption experiments, IR-, and UV-spectroscopy the structure model is confirmed without any doubt. Besides, the Rietveld analysis of the XRD data is the analytical tool to gain more detailed geometric information of the metallosilicate framework. The synthesis procedure is flexible and can be extended to other Me-cations as linker sites. We have prepared isostructural interlayer expanded metallosilicates of similar crystallinity with Ti, Sn, Zn, Eu, and Al as active centers. This method of inserting Me-cations as linkers in hydrous layer silicates shows for the first time that the active sites in the generated microporous silicate framework can be obtained in a controlled manner on well defined T-sites.

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Acta Cryst. (2014). A70, C546
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The famous Miller experiment to model the primordial soup demonstrated that amino acids can form spontaneously as the essential building blocks of life in solutions. It is, however, still an open question how self-recognition processes influence the transformation of these spontaneously formed amino acids in solvents into higher ordered structures in the solid state, thereby creating chiral materials and catalytically competent structures. The understanding of the first steps of molecular self-assembly processes in such environments will thus give important clues towards the understanding of biological evolution. Most of intermolecular interactions are not very strong and their formation is related to and affected by small changes in the molecular structure and the crystallisation conditions. Continuing our investigations on aggregation of substituted aromatic molecules in the solid state, we studied the influence and boundaries of weak directing substituents like deuterium on the aggregation of small molecules. Hydrogen/deuterium (H/D)-exchange, the smallest possible modification of a molecule, is generally seen as a non dominating parameter in the formation of crystal structures of chemical compounds. On the other hand, it could already be shown that the aggregation of molecules in the solid state of polymorphic N-heterocycle systems like pyridine-N-oxide or acridine can be very sensitive to small changes of the isotopic substitution pattern of the selected molecules. Within our project, the molecular aggregation of amino acids in solution with the formation of molecular aggregates and pre-nucleation clusters in deuterated and non-deuterated systems, and in particular the role of the solvent in these processes, will be studied in both experiment and theory.
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