1. Characterization of a Molecule Partially Confined at the Pore Mouth of a Zeotype.
- Author
-
Grosso-Giordano NA, Schroeder C, Xu L, Solovyov A, Small DW, Koller H, Zones SI, and Katz A
- Subjects
- Density Functional Theory, Models, Molecular, Molecular Structure, Particle Size, Porosity, Surface Properties, Calixarenes chemistry, Macrocyclic Compounds chemistry, Organometallic Compounds chemistry, Phenols chemistry, Titanium chemistry
- Abstract
We investigate the interaction between a molecule and a pore mouth-a critical step in adsorption processes-by characterizing the conformation of a macrocyclic calix[4]arene-Ti
IV complex, which is grafted on the external surface of a zeotype (*-SVY). X-ray absorption and13 C{1 H} CPMAS NMR spectroscopies independently detect a unique conformation of this complex when it is grafted at crystallographically equivalent locations that lie at the interface of 7 Å hemispherical microporous cavities and the external surface. Electronic structure calculations support the presence of this unique conformation, and suggest that it is brought about by a specific orientation of the macrocycle that maximizes non-covalent interactions between calix[4]arene upper-rim tert-butyl substituents and the microporous-cavity walls. Our comparative study provides a rare "snapshot" of a molecule partially confined at a pore mouth, an essential intermediate for adsorption into micropores, and demonstrates how surrounding environment controls this confinement in a sensitive fashion., (© 2021 Wiley-VCH GmbH.)- Published
- 2021
- Full Text
- View/download PDF