Coherence transfer signals in the rotational resonance NMR of a spinning single crystal

A recent analysis of rotational resonance lineshapes (M. Helmle et al., J. Magn. Reson. 140, 379-403, 1999) predicted the existence of coherence trans fer signals, which are generated by mechanically induced coherence transfer during the detection process. These signals correspond to the generation o f observable coherences at spin sites that have no magnetization at the beg inning of the observation interval but which acquire coherence while the de tection is underway. The coherence transfer signals disappear for powder sa mples in conventional magic-angle-spinning solid-state NMR experiments. In this Communication, we report the successful detection of coherence transfe r signals in rotor-synchronized experiments performed on a single crystal o f [1,2-C-13(2)]glycine. (C) 2000 Academic Press.