Double quantum NMR

Jelicks, L.A. Gupta, R.K. (1989). Double-quantum NMR of sodium ions in cells and tissues. Paramagnetic quenching of extracellular coherence. J. Magn. Reson. 81,586-592. 

Dalvit C, Bohlen IM, Multiple-Solvent Suppression in Double-Quantum NMR Experiments with Magic Angle Pulsed Field Gradients, Magn. Reson. Chem., 34 829-833, 1996. 

Figure 4.25. Si double quantum NMR spectrum of Si-enriched 25Na20-75Si02 glass. The diagonal peaks are marked by filled circles, and the off-diagonal peaks indicate the connectivities between the structural units (in this case between Q and Q ). From Clock et at. (1998), by permission of Elsevier Science.

NMR studies devoted to this issue exploit two-dimensional zero- or double quantum NMR methods to recouple homonuclear magnetic dipole-dipole interactions in MAS-spectra. The connectivity information then stems from the presence (or absence) of crosspeaks linking resolved resonances attributable to distinct sites. To date, this type of analysis has been predominantly ap-... 

C Dalvit, JM Bohlen. Multiple-solvent suppression in double-quantum NMR experiments with magic angle pulsed field gradients. Magn Reson Chem 34 829-833. 1996. 

Fig. 52 a) Sketch of empty helical stacks formed by shape-persistent macrocycles, b) A pitch angle of Ri60° between adjacent macrocycles was determined from 2D double quantum NMR correlation spectra in agreement with NICS maps, c) Side-chain packing [201]... 

H.W. Spiess, Double-quantum NMR spectroscopy of dipolar-coupled spins under fast magic-angle spinning, in eMagRes, John Wiley Sons, Ltd., 1 (2012), pp. 109—126. 

S. Vega, A. Pines, Operator formalism for double quantum NMR, J. Chem. Phys. 66 (1977) 5624. 

L. Olivier, X. Yuan, A.N. Cormack, C. Jager, Combined Si double quantum NMR and MD simulation studies of network connectivities of binary Na20Si02 glasses new prospects and problems. J. Non-Cryst. Solids 293-295, 53-66 (2001)... 

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