NMR crystallography of extraframework sites in silicon rich zeolites

Abstract:
The project deals with the development of methods for the identification of cations in extraframework tites (active sites) in catalytic systems based on silicon rich zeolites and on their description in sub-nanometer scale. The knowledge of the structure of these sites necessary for the understanding to physicochemical/catalytic properties cannot be obtained from diffraction studies. Thus, methods enabling the description of the system of dehydrated silicate matrix (with one or more skeletal Al atoms) - ligand (mono- or divalent cation) will be developed based on the combination of high resolution solid state NMR spectroscopy and quantum-chemical calculations. The detail knowledge of the arrangement of active sites on the atomic level is necessary for the study of their catalytic properties using quantum-chemical approach. The knowledge of the NMR parameters of individual cations in extraframework positions will enable their identification in materials relevant for application.