Resolution of C-13-F-19 interactions in the C-13 NMR of spinning solids and liquid crystals

Antonioli, G.; Hodgkinson, P.

Abstract

Anomalous line-broadenings of carbon resonances close to F-19 have commonly been reported in the C-13 NMR of liquid crystals and solids. We have previously shown that these effects in static liquid-crystal samples are related to the difficulty of H-1 decoupling in the presence of strong H-1-F-19 dipolar interactions. We here extend this work to spinning samples (both liquid crystals and solids). A number of different line-broadening mechanisms Lire elucidated: analogous decoupling effects, magic angle misset, and F-19 lifetime-broadening. In relatively mobile systems, Such as liquid crystals or soft solids, the limiting factor on 13 C resolution (and the ability to directly quantify the C-13-F-19 interactions) is found to be the efficiency and robustness of the H-1-decoupling. In rigid solids, the lifetime of the F-19 spin-states is found to be an additional critical factor. (C) 2004 Elsevier Inc. All rights reserved.

Citation

Antonioli, G., & Hodgkinson, P. (2004). Resolution of C-13-F-19 interactions in the C-13 NMR of spinning solids and liquid crystals. Journal of Magnetic Resonance, 168(1), 124-131

• Journal Article Type: Article
• Publication Date: 2004-05
• Journal: Journal of Magnetic Resonance
• Print ISSN: 1090-7807
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 168
• Issue: 1
• Pages: 124-131