Spin decoupling and particular pulse sequences

NMR instruments have accommodated numerous advances to facilitate spectral interpretation. Thus it is possible to cancel the effect of an existing spin-coupling between neighbouring nuclei. This spin decoupling technique is based on the statement that a nucleus in resonance does not always conserve the same spin state with time. This uninterrupted and fast transfer between different states induces a global effect upon the neighbouring nuclei. 

Fourier transform NMR at high fields Bq = 17.6T for the study of H at 750 MHz) has considerably extended the potential of this method. This is due to an increase in acquisition speed and rapid computation of spectra. 

A variety of experiments based upon particular pulse sequences can be applied to a sample to produce a specific form of NMR signals. For example, the 90-FID pulse sequence rotates the net magnetization down into the xy-plane, through which the relaxation times of the nuclei can be determined. Amongst the more 

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