Intrazeolite organometallics, internal metal guests

The process of loading zeolites with organometallie complexes always brings to the forefront the question of internal versus external confinement of the metal guest. In this paper we present some experiments based on size exclusion, metal loading and intrazeolite chemistry which in conjunction with FT-FAR-IR, EPR and UV-visible reflectance spectroscopy, critically probe the question of internal versus external location for the case of five representative organometallics,... 

Thus by using Co2(C0)8 as a representative organometallic guest, and a combination of size exclusion experiments and intrazeolite oxidation chemistry, as probed through the far-IR cation spectra of sodium and acid faujasites and A-zeolites, one is able to distinguish between internal and external confinement of the metal guest(s) in the zeolite. 

Overall it is quite clear, that a combination of epr spin-probes, UV-vis reflectance spectroscopy, size exclusion and intrazeolite oxidation experiments are able to effectively differentiate those organometallic-zeolite impregnations which place metal guests within the internal voids of the zeolite compared to those on the external surface of the zeolite lattice. 

Intrazeolite organometallics and coordination complexes internal vs. external containment of metal guests... 

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