Two-pulse ESEEM spectra (cosine FT) of myosin·M-n·AMPPNP (trace 1), Mn·AMPPNP (trace 2), Mn·ATP (trace 3), Mn·ADP (trace 4), and myosin·Mn·ADP·AlF4 (trace 5). Experimental conditions: νmw = 30.108 GHz (traces 1–4) and 30.136 GHz (trace 5); Bo = 1070.3 mT (traces 1 – 4) and 1072.8 mT (trace 5); mw pulses, 8 and 14 ns; temperature, 15 K. Assignments of various features to different magnetic nuclei are indicated.