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13C NMR of Liquid Crystals with Different Proton Homonuclear Dipolar Decoupling Methods

✍ Scribed by B.M. Fung; Konstantin Ermolaev; Youlu Yu

Publisher
Elsevier Science
Year
1999
Tongue
English
Weight
106 KB
Volume
138
Category
Article
ISSN
1090-7807

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✦ Synopsis

The effect of several new homonuclear dipolar decoupling methods (frequency-switching Lee-Goldburg decoupling and two sequences based on z-rotational decoupling) on the 13 C spectra of liquid crystals has been studied, and the results are compared with those obtained by using two well-established methods (MREV-8 and BLEW-48). For benzene dissolved in two liquid crystalline solvents, BLEW-48 gives the best spectral resolution. The BLEW-48 sequence has also been applied to the 2D method of proton-encoded local field (PELF) spectroscopy to study a bulk liquid crystal, 4-n-pentyl-4-cyanobiphenyl (5CB). The results are compared with those obtained by using MREV-8, and it is suggested that the BLEW-48 sequence may be preferable to MREV-8 for application in the PELF method.

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