Three-dimensional measurements of the nuclear magnetic resonance chemical shift and a new analytic data transform for the shift anisotropy

Three-dimensional measurements of the C-13 nuclear magnetic resonance (NMR) chemical shift in methyl-alpha-D-glucopyranoside are presented. One dimens ion measures the isotropic shift under ordinary magic angle spinning. In th e remaining two dimensions, the chemical shift anisotropy (CSA) is recouple d in two complementary ways. An analytic transform is constructed which tak es the time-domain data directly to the three isotropic shift parameters, w hich can then be read off the resulting plot. The possibility of using such an experiment to resolve chemical sites by the CSA alone in powdered sampl es is discussed. (C) 2000 American Institute of Physics. [S0021-9606(00)005 19-5].