th  - 1988 - 51st ENC Conference

TUE ii'00 J
WATER SUPPRESSION TECHNIQUES FOR THE GENERATION
OF PURE PHASE NMR SPECTRA
Vladimir Sklen~
Institute of Scientific Instruments, Czechoslovak
Academy of Sciences, CS-612 64 BRNO, Czechoslovakia
A large variety of selective excitation techniques are available
for suppression of the intense H20 resonance in the NMR spectra
of water soluble compounds. However, only a few methods yield spec-
tra that are free of phase (and cosequently baseline) distorsions
and can be applied in the pure absorption 2D NMR experiments. New
class of two stage selective excitation techniques that offer very
good water suppression, ideal phase profile and different amplitude
profiles will be discussed. These methods use time shared hard pulse
sequences or combinations of soft and hard pulses and take advan-
tage of the phase cycling to achieve desired properties. Application
to the measurement of pure phase 2D NMR spectra of small proteins
and DNA fragments will be presented.
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