Building Blocks and Elements - Part Two

This section focuses on the coupling evolution that occurs during the pulse sequences of heteronuclear correlation experiments. Because polarization transfer is a requirement of intensity optimized heteronuclear correlation spectroscopy this section also acts as a short introduction to coherence transfer by polarization transfer. A coherence transfer from a sensitive nucleus, e.g. in most experiments, to a nucleus contributes a gain of signal intensity. To obtain the required antiphase coherence for the transfer step the coherence must evolve exclusively by heteronuclear coupling during a free precession periods. This can only be assumed in theoretical spin systems. In real samples three aspects make this ideal approach more difficult  

NMR Spectroscopy Data Acquisition, Second Edition. C. Schorn, B. Taylor Copyright 2004 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 3-527-31070-3 

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