Residual dipolar couplings in MAS and MQMAS NMR spectra of quadrupolar nuclei
نویسندگان
چکیده
Ž . We report the first observation of residual dipolar couplings in magic-angle-spinning MAS and multiple quantum Ž . magic-angle-spinning MQMAS NMR spectra of half-integer quadrupolar nuclei. In particular, the fine spectral splittings observed in the B MAS spectrum of crystalline triethanolamine borate are attributed to the residual B–N dipolar coupling, which is not completely averaged by MAS. This interpretation is corroborated by the observation of an asymmetrical doublet in the B MQMAS spectrum. q 1999 Elsevier Science B.V. All rights reserved.
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