Six pulse sequences are described, all based on the stimulated echo, for use in high resolution diffusion-ordered spectroscopy (HR-DOSY). HR-DOSY requires spectra with clean baselines, pure phases and lineshapes that are independent of field gradient pulse amplitude. Lineshape problems arising from the static field perturbations caused by field gradient pulses and phase errors caused by zero quantum coherence in strongly coupled spin systems are discussed, and the performance of the six sequences is compared. Pulse sequences which use balanced pairs of antiphase field gradient pulses show significant advantages. (C) 1998 John Wiley & Sons Ltd.
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