XAFS, IR, Raman and UV-Vis Characterization of Framework Ti(IV) Species in Ti-Silicalites
نویسندگان
چکیده
The main results obtained by using IR, Raman and W-Vis techniques concerning the structure of the Ti(IV) center in Ti-silicalite is briefly reviewed and discussed with recent XAFS results. The Ti(1V) is in tetrahedral coordination in vacuo and expands its coordination sphere upon interaction with adsorbates. Present EXAFS results indicate, for the dehydrated sample, a fust shell coordination number higher then four (4.45 f: 0.3), suggesting, in a fraction of sites, the substitution of a bndged oxygen with two OH groups.
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