Fig. 7: Quantitative comparison of photoisomerization quantum yields.
From: A photochemical method to evidence directional molecular motions
Comparison of the photochemical behavior of restricted macrocycle 2 and molecular motor 3. The indanone rotor and part of the benzothiophenone stator are colored purple and the biaryl moiety is colored dark red. Clockwise rotations and corresponding quantum yields are depicted by blue arrows and values and counterclockwise rotations are depicted in orange. a Because of the macrocyclization light-induced motions are restricted to half space I (grey half circle and solid arrows) or II (dashed grey half circle and dashed arrows) only in macrocycle 2. Quantum yield values are corrected for the macrocyclization effect as shown in Fig. 6. b Quantum yields for E to Z and Z to E photoisomerization of 3-(S)-(Sa) (top) and 3-(S)-(Ra) (bottom). Comparison with macrocycle 2 reveal the theoretically predicted overall unidirectionality (blue arrows) for 3-(S)-(Sa) and 3-(S)-(Ra). A higher degree of unidirectionality is observed for 3-(S)-(Sa) as opposed to 3-(S)-(Ra), for which an increased backwards rotation takes place.
