Probing Interactions of N-Donor Molecules with Open Metal Sites within Paramagnetic Cr-MIL-101: A Solid-State NMR Spectroscopic and Density Functional Theory Study.
Understanding host-guest interactions is one of the key requirements for adjusting properties in metal- organic frameworks (MOFs). In particular, systems with coordinatively unsaturated Lewis acidic metal sites feature highly selective adsorption processes. This is attributed to strong interactions...
| Published in: | Journal of the American Chemical Society Vol. 140; no. 6; pp. 2135 - 2145 |
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| Main Authors: | , , , , , , , , , |
| Format: | Article |
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American Chemical Society
2/14/2018
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| Subjects: | |
| Online Access: | View this record in EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=128050495&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 128050495 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 2/14/2018 vid: 140 iid: 6 pid: 997 pub: American Chemical Society artinfo: ui: 128050495 10.1021/jacs.7b10148 ppf: 2135 ppct: 10 formats: tig: atl: Probing Interactions of N-Donor Molecules with Open Metal Sites within Paramagnetic Cr-MIL-101: A Solid-State NMR Spectroscopic and Density Functional Theory Study. aug: au: Wittmann, Thomas Mondal, Arobendo Tschense, Carsten B. L. Wittmann, Johannes J. Klimm, Ottokar Siegel, Renée Corzilius, Björn Weber, Birgit Kaupp, Martin Senker, Juergen affil: Inorganic Chemistry III, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany Institute of Chemistry, Theoretical Chemistry/Quantum Chemistry, Technical University of Berlin, Sekr. C7, Straße des 17. Juni 135, 10623 Berlin, Germany Institute of Physical and Theoretical Chemistry and Institute of Biophysical Chemistry, Goethe University Frankfurt, Max-von-Laue-Straße 7-9, 60438 Frankfurt am Main, Germany Inorganic Chemistry II, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany su: Metal-organic frameworks Density functional theory Diethylamine Thermogravimetry Hyperfine coupling Nuclear magnetic resonance sug: subj: Metal-organic frameworks Density functional theory Diethylamine Thermogravimetry Hyperfine coupling Nuclear magnetic resonance ab: Understanding host-guest interactions is one of the key requirements for adjusting properties in metal- organic frameworks (MOFs). In particular, systems with coordinatively unsaturated Lewis acidic metal sites feature highly selective adsorption processes. This is attributed to strong interactions with Lewis basic guest molecules. Here we show that a combination of C MAS NMR spectroscopy with state-of-the-art density functional theory (DFT) calculations allows one to unravel the interactions of water, 2-aminopyridine, 3-aminopyridine, and diethylamine with the open metal sites in Cr-MIL-101. The C MAS NMR spectra, obtained with ultrafast magic-angle spinning, are well resolved, with resonances distributed over 1000 ppm. They present a clear signature for each guest at the open metal sites. Based on competition experiments this leads to the following binding preference: water < diethylamine ≈ 2-aminopyridine < 3-aminopyridine. Assignments were done by exploiting distance sum relations derived from spin-lattice relaxation data and C{¹H} REDOR spectral editing. The experimental data were used to validate NMR shifts computed for the Cr-MIL-101 derivatives, which contain CrO clusters with magnetically coupled metal centers. While both approaches provide an unequivocal assignment and the arrangement of the guests at the open metal sites, the NMR data offer additional information about the guest and framework dynamics. We expect that our strategy has the potential for probing the binding situation of adsorbate mixtures at the open metal sites of MOFs in general and thus accesses the microscopic interaction mechanisms for this important material class, which is essential for deriving structure-property relationships. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2018 holdings: @attributes: islocal: N |
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