W-band PELDOR with 1Â kW microwave power: Molecular geometry, flexibility and exchange coupling

► We use a home-built 1 kW, W-band pulsed EPR spectrometer for PELDOR measurements. ► We obtain PELDOR data with a high degree of orientation selectivity. ► PELDOR correlations between all three canonical orientations is achieved. ► Relative orientations of nitroxide spin labels are quantitatively determined.