Enhanced versions of heteronuclear chemical shift correlation experiments which yield high-quality spectra with efficient suppression of extra peaks arising from strong coupling effects are proposed. The enhanced pulse sequences feature properly designed filtering schemes inserted during preparation, or prior to acquisition, or at both places depending on the particular experiment. These modifications extend the applicability of existing methods, since they exclude misinterpretation of spurious peaks and allow unambiguous assignment of the desired correlations. The general applicability of the filtering method is noteworthy; both scalar- and dipolar-correlated experiments with both X and 1H detection using phase cycling or gradient pulses for coherence selection can be freed of strong coupling artifacts.
Copyright 1999 Academic Press.