Survey of NMR Methods

Among spatial reorientation techniques, one can find MAS, OMAS, variable angle spinning (VAS) and switched angle spinning (SAS) techniques. Mechanical spinning of LC materials, which has dated back to the early seventies,63,64 can control the averaging of anisotropic spin interactions 

Since 5 = 90°, only the cos (2cort + 2cp) term contributes, giving sidebands at even multiples of the spinning frequencies. 

Proton-carbon HETCOR experiment has recently been done on a liquid crystal97 to observe long-range proton-carbon correlations. In this 

A deuterium 2D Q-COSY experiment has recently been proposed,112 using a n/2 — t — n —12 pulse sequence (Fig. 8(a)), to study weakly oriented systems. The ID deuterium NMR spectrum obtained in a simple one-pulse experiment 

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