Fig. 10: EPR and DNP pulse sequences.

Schematic diagrams illustrating the pulse sequences used in the DNP and EPR experiments. For the DNP experiments either single frequency cw radiation or inverting pulsed radiation (rectangular or chirp) was used to create a polarisation gradient across the sample. DNP enhancements were taken by measuring the integral of the FID with and without microwave radiation. ELDOR experiments were used to give a qualitative indication of electron polarisation across the line as a function of pumping frequency.