Nuclear magnetic resonance chemical shift interaction

Park, K.D., Guo, K., Adebodun, F., Chiu, M.L., Sligar, S.G., et al. Distal and proximal ligand interactions in heme proteins correlations between C-O and Fe-C vibrational liequencies, oxygen-17 and carbon-13 nuclear magnetic resonance chemical shifts, and oxygen-17 nuclear quadrupole coupling constants in C O- and CO-labeled species. Biochemistry 30, 2333-2347 (1991)... 

A solution-state and solid-state nuclear magnetic resonance study of the complex and its separate components in both their neutral and ionized (TMP hydrochloride and SMZ sodium salt) forms was undertaken in order to elucidate the TMP-SMZ interactions. Inspection of the data for the complex in the solid state shows that the 13C chemical shifts are consistent with the ionic structure proposed by Nakai and coworkers105 (14). Stabilization of the complex is achieved by the resulting ionic interaction and by the formation of two intermolecular hydrogen bonds. 

Evidence for the interaction between tributylamine and BN nanotubes has been obtained by nuclear magnetic resonance spectroscopy. We have studied the H and 13C NMR spectra of tributylamine-functionalized BN nanotubes in comparison with the spectra of tributylamine. We observe a small increase in the H chemical shift by 0.02 ppm in the amine-BN adduct. In the case of nC NMR spectra, we observe a significant increase in the chemical shifts of the y and S carbons by 0.4 ppm and a decrease in the chemical shift of the P carbon atom by 0.3 ppm. The chemical shift of the acarbon is also higher in the amine-BN adduct by 0.1 ppm. The changes in the H and L1C spectra of tributylamine found on interaction with BN are comparable to those reported in the literature for similar complexes.17,18... 

Nuclear magnetic resonance spectroscopy and x-ray crystallography have greatly enriched our understanding of how proteins fold, recognize other molecules, and catalyze chemical reactions. Nuclear magnetic resonance spectroscopy reveals the structure and dynamics of proteins in solution. The chemical shift of nuclei depends on their local environment. Furthermore, the spins of neighboring nuclei interact with each other in ways that provide definitive structural information. 

A different class of phenomena can be related to the interaction of the electronic polarization density and induced current with the nuclei. Thus the chemical shifts in nuclear magnetic resonance (NMR) spectroscopy are interpreted in terms of magnetic shielding of the electrons, perturbed by a static magnetic field, at those nuclei possessing an intrinsic magnetic moment [7]. 

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