Influence of proton coupling on symmetry-based homonuclear 19F dipolar recoupling experiments

Title data

Zehe, Christoph S. ; Siegel, Renée ; Senker, Jürgen:
Influence of proton coupling on symmetry-based homonuclear 19F dipolar recoupling experiments.
In: Solid State Nuclear Magnetic Resonance. Vol. 65 (2015) . - pp. 122-131.
ISSN 0926-2040
DOI: https://doi.org/10.1016/j.ssnmr.2014.12.002

Official URL:

Abstract in another language

We study the efficiency of two symmetry based homonuclear F-19 double-quantum recoupling sequences for moderate (R14(2)(6)) and ultra-fast (R14(4)(5)) MAS under the influence of strong H-1-H-1 and H-1-F-19 dipolar interactions and H-1 continuous wave decoupling. Simulations based on various spin systems derived from the organic solid 1,3,5-tris(2-fluoro-2-methylpropionylamino)benzene (F-BTA), used as a model system, reveal that the strong-decoupling limit is not accessible even for moderate spinning speeds. Additionally, for the no-decoupling limit improved DQ efficiencies are predicted for both moderate and ultra-fast MAS. Strong perturbations of build-up curves can be avoided by additional stabilisation through supercycling. Additional H-1 cw decoupling during F-19 recoupling rapidly reduces the maximum DQ efficiency when deviating from the no-decoupling limit. These effects were confirmed by experimental data on F-BTA. For moderate spinning the influence of H-1-H-1 and H-1-F-19 couplings is markedly stronger compared to ultra-fast MAS. For the latter case those influences reduce to a constant scaling if only short excitation times up to the first minimum are taken into account Based on this analysis the experimental build-up curves of 1,3,5-tris(2-fluoro-2-methylpropionylamino)benzene can be refined with homonuclear F-19 spin systems which allow to probe even subtle structural differences for the fluorine atoms of F-BTA. (C) 2014 Elsevier Inc. All rights reserved.

Further data

Item Type:	Article in a journal
Refereed:	Yes
Additional notes:	ISI:000350874400015
Keywords:	Solid-state NMR spectroscopy; 19F homonuclear DQ recoupling; Symmetry based dipolar recoupling; 1H decoupling
Institutions of the University:	Faculties > Faculty of Biology, Chemistry and Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Inorganic Chemistry III Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Inorganic Chemistry III > Chair Inorganic Chemistry III - Univ.-Prof. Dr. Jürgen Senker Faculties
Result of work at the UBT:	Yes
DDC Subjects:	500 Science 500 Science > 540 Chemistry
Date Deposited:	18 Mar 2021 08:08
Last Modified:	07 Feb 2023 10:06
URI:	https://eref.uni-bayreuth.de/id/eprint/64073