Magic-angle spinning-nuclear magnetic resonance

5 Magic Angle Spinning-Nuclear Magnetic Resonance 

In solids, the averaging due to fast movement will not occur, or even if it does, occurs partially then, the effects of direct dipolar couplings can be observed [72,73], The direct magnetic dipolar interaction between nuclear spins causes a nucleus with spin projection, ml5 to produce a magnetic field in the z-axis, Bimc, at a distance, R, given by the following expression [12] 

9 is the angle between the vector connecting the dipoles and the external field or the angle between the external field and the principal axis of the molecule 

Additionally, anisotropic chemical shift effects will also be present in the spectrum due to the nonexistence of molecular tumbling. This means that, since in solids the atoms and molecules are not moving, they do not change the orientation. Since the ability of the applied field to generate electron currents depends on the orientation of the nuclei relative to the applied field, the chemical shift depends on orientation, and since in solids this effect is not averaged out, it will contribute to the peak broadening. The chemical shift anisotropy also varies with the angle, 9, 

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Gan, Z. (2001) Satellite transition magic-angle spinning nuclear magnetic resonance spectroscopy of half-integer... 

The Al magic angle spinning nuclear magnetic resonance (MASNMR) spectra were acquired using a 30 pulse at 0.1 sec. intervals. About 5000 to 7000 scans were acquired on a Bruker AM-400. The chemical shift is relative to aluminum nitrate in water solution which contains A1(H20)6. ... 

L.B. Moran, J.K. Berkowitz, J.P. Yesinowski, F and P magic angle spinning nuclear magnetic resonance of antiomony (III) doped fluorapatite phosphors Dopant sites and spin diffusion, Phys. Rev. B 45 (1992) 5347-5360. 

K. J. D. MacKenzie and R. H. Meinhold, A Mg magic-angle spinning nuclear magnetic resonance study of the thermal decomposition of magnesium carbonate. /. Mater. Sci. Lett, 1993,12,1696-1698. 

R. Lefort, J. W. Wiench, M. Pruski and J.-P. Amoureux, Optimization of data acquisition and processing in Carr-Purcell-Meiboom-Gill multiple quantum magic angle spinning nuclear magnetic resonance. /. Chem. Phys., 2002,116, 2493-2501. 

MACT MAS-NMR Maximum achievable control technology Magic-angle spinning nuclear magnetic resonance... 

C. Dhalluin, C. Boutillon, A. Tartar and G. Lippens, Magic angle spinning nuclear magnetic resonance in solid-phase peptide synthesis, J. Am. Chem. Soc., 1997, 119, 10494-10500. 

Z. Zhou, B. G. Sayer, D. W. Hughes, R. E. Stark and R. M. Epand, Studies of phospholipid hydration by high-resolution magic-angle spinning nuclear magnetic resonance,... 

To draw conclusions concerning the templating effect of different molecules, comparable conditions for the crystallization process must be used. In this paper we present a systematic investigation on the effect of mono-, di- and tri-n-alkylamine and tetraalkylammonium compounds (alkyl = C. - C,) upon the rate of crystallization, yield and the properties of the products. Also the field of a template-free synthesis is studied. The products were characterized by magic-angle-spinning nuclear magnetic resonance spectroscopy (MAS NMR) and X-ray diffraction. 

Cross Polarization/Magic Angle Spinning Nuclear Magnetic Resonance (CP/MAS NMR) Spectroscopy... 

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