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Line broadening in high-resoln. NMR spectra caused by heteronuclear scalar coupling is described, and various adiabatic frequency-modulated decoupling schemes in high-resoln. NMR spectroscopy are compared. The CHRIP-95 decoupling scheme, which uses a linea ...
A novel technique is described that allows one to measure cross-relaxation rates (Overhauser effects) between 2 selected nuclei in high-resoln. NMR. The 2 chosen sites are irradiated simultaneously with the sidebands of an amplitude-modulated radiofrequenc ...
New exptl. methods are presented that allow one to measure cross-correlation between the fluctuations of dipolar interactions and chem. shift anisotropy (CSA) in scalar coupled systems with two and three spins I = 1/2 in isotropic soln. The methods involve ...
Cross-correlation between proton chem. shift anisotropy and proton-proton dipolar interactions is shown to be an important relaxation mechanism. Cross-correlation leads to a partial conversion of Zeeman order into longitudinal two-spin order. The build-up ...
New NMR techniques are described for transferring transverse magnetization between scalar-coupled nuclei in the rotating frame. The methods involve simultaneous spin-locking of two selected spins A and X, using cosinusoidal modulation of the radio frequenc ...
The performance of several different two-dimensional NMR methods for the measurement of carbon-proton dipolar couplings in liquid crystalline phases is analyzed. Proton-detected local field spectroscopy allows the measurements of short range C-H couplings, ...
By analogy to heteronuclear systems, coherence can be transferred adiabatically in the rotating frame between two selected spins I and S belonging to a homonuclear network of scalar-coupled spins. In contrast to cross polarization with const. radiofrequenc ...
An anal. was made of the effects of nonexponential transverse relaxation during the free precession periods of 2-dimensional NMR expts. The presence of cross-correlation between various interactions that cause relaxation, such as chem. shift anisotropy and ...
Cross-correlation between pairs of dipole-dipole interactions may lead to a partial conversion of longitudinal Zeeman magnetization into longitudinal three-spin order, which can be obsd. selectively by using a triple-quantum filter in conjunction with two- ...
A recently developed approach for the anal. of cross-peak multiplets was applied to 2-dimensional correlation spectra of the binary alkaloid vinblastine and the cyclic undecapeptide cyclosporin A. The exptl. multiplet patterns are encoded in a manner that ...
