FIGURE 3. Operation of a molecular information ratchet.

a, Change in the E:Z ratio (E-1 (%), the amount of the 'open gate' form of the sample, shown by purple diamonds) and the dba:mba ratio (dba-occupancy (%), shown by dark blue squares) that occurs during irradiation of 1 at 350 nm in CD₃OD, 298 K: I, pristine E-1; II, after 25 min (PSS), no added benzil; III, after a further 20 min (PSS) with 1 equiv. benzil; IV, after a further 40 min with 5 equiv. benzil plus a further 15 min (PSS) with 10 equiv. benzil. A small amount of photodegradation (<2%) occurs over the course of the experiment, and the error in the final E:Z and dba:mba ratios is 2%. b, Expansion showing the small increase (2–5%, see Supplementary Information) in dba compartment occupancy that occurs during the first five minutes of irradiation in the absence of benzil. c, ¹H NMR spectral window (H_s'+S', H_s and H_S, 600 MHz, CD₃OD, 298 K) in which the changes in both the E:Z and dba:mba ratios can be seen during the photochemistry experiment.