Fundamentals of Multiple-Quantum Magic-Angle Spinning NMR on Half-Integer Quadrupolar Nuclei
نویسندگان
چکیده
منابع مشابه
High-resolution multiple quantum MAS NMR spectroscopy of half-integer quadrupolar nuclei
We demonstrate the utility of a two-pulse sequence in obtaining high-resolution solid state NMR spectra of half-integer quadrupolar nuclei with magic-angle-spinning (MAS). The experiment, which utilizes multiple/single-quantum correlation, was first described in a different form by Frydman and Harwood [J. Am. Chem. Soc. 117 (1995) 5367] and yields high-resolution isotropic NMR spectra where shi...
متن کاملReintroducing anisotropic interactions in magic-angle-spinning NMR of half-integer quadrupolar nuclei: 3D MQMAS.
Selective reintroduction of anisotropic interactions such as the chemical shift anisotropy (CSA) and homonucler dipolar (HMD) coupling were implemented in a high-resolution NMR spectroscopy for half-integer quadrupolar nuclei. Rotary resonance recoupling (R(3)) combined with the multiple-quantum magic-angle spinning (MQMAS) in a three-dimensional (3D) experiment provides not only site-specific ...
متن کاملDecoupling-induced recoupling in multiple-quantum magic-angle-spinning NMR spectra of quadrupolar nuclei
We report the observation of a new decoupling-induced recoupling phenomenon in multiple-quantum magic-angle-spinŽ . ning MQMAS NMR spectra of half-integer quadrupolar nuclei. The origin of the effect is identical to the second-order Ž . recoupling between dipolar and anisotropic chemical shielding interactions under continuous-wave CW spin decoupling, w Ž . x which is first observed by Ernst et...
متن کاملResidual dipolar couplings in MAS and MQMAS NMR spectra of quadrupolar nuclei
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 M...
متن کاملSolid state separated-local-field NMR spectroscopy on half-integer quadrupolar nuclei: principles and applications to borane analysis.
New multidimensional NMR methods correlating the quadrupolar and heteronuclear dipolar interactions affecting a half-integer quadrupolar spin in the solid state are introduced and exemplified. The methods extend separated-local-field magic-angle spinning (SLF MAS) NMR techniques that have been used successfully in spin-(1)/(2) spectroscopy to the study of S >/= (3)/(2) nuclei. In our implementa...
متن کامل