NOESY block

NOESY(Nuclear Overhauser Effect SpectroscopY)is a mixing process to transfer polarisation between spins via dipolar coupling or chemical exchange.

The NOESY block is formed from two 90° pulses separated by a delay period known as the mixing time (t_m).

Before the first 90° pulse we have transverse in phase magnetisation of the initial spin.

The 90° pulse creates longitudinal magnetisation (I1z).

Magnetisation is transferred to other spins via dipolar coupling or exchange processes during the mixing time.

The second 90° pulse creates transverse magnetisation of the relayed nucleus.