P. Trautner and K. Woelk, Phys. Chem. Chem. Phys. 4, 5973-5981 (2002).

• The NMR measurement of molecular diffusion with magnetization-grating rotating-frame imaging (MAGROFI) is improved by utilizing the tightest magnetization grating that is but resolved by the imaging data (Nyquist grating). The tightness of a Nyquist grating depends on the digital image resolution, and a fixed relationship is found between grating preparation and rotating-frame imaging.

• If applied to toroid cavity NMR detectors, phase-cycled fast two-transient NYGROFI (Nyquist-grating rotating-frame imaging) reduces the experimental time to minutes or only seconds depending mainly on relaxation times. For the compensation of radiofrequency pulse deficiencies, gratings are prepared with a pulse train similar to the one used for data acquisition. The NYGROFI transients are supplemented by a saturation-recovery sequence to compensate for T1 relaxation that inevitably occurs during the experiment.

• From a numerical finite-difference approach that simulates the effects of diffusion during both the evolution time and the pulse sequences, diffusion coefficients are accurately determined by fitting simulated nutation interferograms to experimental data.

• Diffusion coefficients of individual components in mixed systems are measured with a new difference spectroscopy technique

K. Woelk, November 25, 2002