Using NOE to Map Nearby Nuclei

Nuclear Overhauser enhancement, or NOE, shows how irradiation of one spin-active nucleus can change the signal of nearby nuclei. These nuclei do not have to be chemically bonded or connected through J-coupling. The effect comes from through-space interactions between nuclear spins.

NOE gets weake...

Irradiating a spin-active nucleus can alter the signal intensity of a neighboring nucleus that need not be chemically bonded or J-coupled to it.

This through-space phenomenon called nuclear Overhauser enhancement, or NOE, decreases with the internuclear distance and is usually not seen beyond 4 angstroms.

Here, dipole–dipole i...