A. Lange, S. Luca and M. Baldus (2002) J. Am. Chem. Soc. 124 9704-9705. (Link to Article)
Minimum labelling: 15N, 13C
Magnetisation is transferred from 1H to 13C via cross polarisation. In three sucessive steps it is first transferred back to 1H, then to other 1H nuclei nearby, and finally back to 13C for detection. The chemical shift is evolved on the 13C nuclei following the initial cross polarisation and detected on the 13C nuclei at the end, resulting in a 2D carbon-carbon spectrum, but which encodes information about proton-proton distances of the protons attached to the carbon atoms.
This experiment is particularly useful for obtaining proton-proton structural restraints which can be used in protein structure calculations.