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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 ...
A technique is proposed which simplifies the study of spin-lattice relaxation in multilevel nuclear spin systems. The introduction of non-participating "spy" nuclei, which interact with the nuclei under investigation through scalar or dipolar coupling, m ...
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 ...
A new method is presented for decoupling spins with S = 1 like D in anisotropic media while observing other spins such as residual protons in partly deuterated samples. The carrier frequency of a weak radiofrequency (RF) field is applied near the center of ...
The heteronuclear cross-polarization efficiency in the rotating frame can be improved by sweeping the radiofrequency amplitude adiabatically through the Hartmann-Hahn condition. The enhancement is particularly significant for strongly coupled IS spin syste ...
Dipolar-coupled spectra of mols. dissolved in liq. cryst. solvents were analyzed by applying pattern recognition procedures to 2-dimensional z-filtered correlation spectra (z-COSY). Transitions that share common common energy levels can be recognized as su ...
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 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 ...
A novel spin-echo expt. is proposed that uses semiselective Gaussian pulse cascades for refocusing in systems with homonuclear couplings. The expt. allows one to obtain evdience of differential T2 effects due to cross-correlation of proton chem. shift anis ...
A soln. is presented to the problem of phase dispersion in the resultant magnetization for pulses used for high-resoln. NMR work by demonstrating how a Gaussian pulse having an on-resonance flip angle of 270 Deg has much improved phase properties over the ...
