Narrowband excitation of H-2 powder pattern and its application to H-2 1D exchange sample-turning NMR

Frequency-selective narrowband excitation of the H-2 powder pattern was exa mined. Selection of a single spectral band with a linewidth of ca. 15 kHz w as achieved by a narrowband H-1 -->, H-2 cross polarization by using the ti me-averaged precession frequency method. Further narrowing with a ca. 5 kHz linewidth is achieved by DANTE irradiation. The narrowband excitation was applied to transform a recently developed 2D spin-exchange method for obtai ning structural information (Chem. Phys. Lett. 260, 159, (1996)) into its 1 D analogue. The determination of the D-C-D bond angle was demonstrated for alpha-glycine-[2,2-d(2),]. Further, the intermolecular polarization transfe r between two deuterons separated by 0.299 nm was detected with the mixing time of 500 ms. (C) 1999 Academic Press.