Modulation pulse interferograms

In most pulsed NMR experiments, the rf field is applied off-resonance. Modulated pulse interferograms (Fig. 2.4(e), 2.5(a), 2.6(a), and 2.7(a)) arise because the vectors of transverse magnetization do not precess with a constant phase shift of itj2 relative to the vector Bj. This is demonstrated in Fig. 2.8. The transverse magnetization is then a resultant of two components, t>(f) with a phase shift of n/2 relative to B, and u(r) in phase with Bt ... 

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