One of the most significant advances in modern high-field NMR has been the development of multidimensional spectroscopy to make tractable complex spectra. As such, we are actively working to implement more advanced multidimensional correlation and decoupling pulse sequences to make zero-field NMR as rich a spectroscopy as its high-field counterpart. The figure to the right shows a 2-dimensional spectrum taken at zero-field using a pulse sequence analogous to that of high field COrrelation SpectroscopY (COSY). The spectrum clearly shows that the lower frequency peaks are not correlated with the higher frequency peaks, indicating that the two sets of peaks arise from different isotopomers (i.e. 1-13C-ethanol vs. 2-13C-ethanol). Having verified that resolution and signal are sufficient in this model system, more complicated multi-dimensional pulse sequences to obtain additional information about complex liquids, biomolecules, and novel materials will soon follow.
Dmitry Budker (UC Berkeley, Physics)