HIGH-QUALITY 1D SPECTRA BY IMPLEMENTING PULSED-FIELD GRADIENTS AS THECOHERENCE PATHWAY SELECTION PROCEDURE

This review covers several high-resolution NMR methods, including sele ctive excitation, gradient selection and inverse spectroscopy. In this way, clean 1D spectra can be quickly obtained without extreme stabili ty conditions because the classical difference spectroscopy is not inv olved. In addition, accurate NMR parameters can be easily extracted fr om such spectra in short measuring times, with high digital resolution and minimum data storage. For these reasons, these 1D experiments are a very useful alternative to multi-dimensional experiments in structu ral and/or conformational studies of small- and medium-sized molecules when a limited amount of information is desired, All these experiment s are described using the shift operator formalism in order to predict a suitable gradient ratio that rephases the desired magnetization and to analyse the inherent sensitivity losses due to the gradient select ion procedure compared with the conventional phase cycle procedure.