| abstract |
A new two-dimensional NMR carbon-proton chemical shift correlation experiment, the MAS-J-HMQC experiment, is proposed for rotating solids. The magnetization transfer used to obtain the correlations is based on scalar heteronuclear J couplings. The 2D map provides through-bond chemical shift correlations between directly bonded proton carbon pairs in a similar way to corresponding high-resolution liquid state experiments. The transfer through J coupling is shown to be efficient and more selective that those based on heteronuclear dipolar couplings. The experiment, which works at high MAS spinning rates, yields the unambiguous assignment of the proton resonances. The experiment is demonstrated on several organic compounds. |