EXPERIMENTAL ASPECTS OF MULTIDIMENSIONAL EXCHANGE SOLID-STATE NMR

A five-pulse sequence for two-dimensional exchange H-2 NMR that results in improved processability of the obtained spectra is presented, together with the phase cycle necessary to eliminate unwanted signal contributions. The scheme of the three-dimensional Fourier transformation to yield pure-absorption-mode three-dimensional H-2 NMR spectra is presented, and the off-resonance measurement of multidimensional H-2 NMR experiments is discussed. Furthermore, the phase cycles of six- and eight-pulse sequences for the acquisition of undistorted three-dimensional H-2 NMR spectra are derived from the phase cycles of the 2D pulse sequences. Differences in the phase cycles for spin-1/2 nuclei, such as C-13, and spin-1 nuclei, such as H-2, are explicitly addressed. (C) 1995 Academic Press, Inc.