Fig. 1:

(A) Experimental EPR spectrum (integrated from the first derivative) of ANCOOT in toluene at 100K (black line) and its hyperpolarized EPR spectrum recorded for 2.5 μs after a 355 nm laser pulse (blue line) and integrated using a boxcar averager over 0.3 μs (see SI for experimental details). The gain factor of −100 for the Boltzmann signal represents the ESP enhancement obtained from time resolved experiments (TREPR), see appendix 4. (B) Plot of the RQM selectivity factor, R_D1 (black squares), and the corresponding values of P_e (red squares) as a function of the exchange parameter, ∣J_CR∣ (J_CR<0), for the case of pure RQM, i.e., process (ii) (scheme 1). N.B. solid black and dashed red interpolating lines are provided as guides to the eye.