A photochemical rotor bias in dual molecular motors

Inspired by the exceptional control over molecular motion in biological machinery, artificial molecular motors capable of unidirectional rotation have been developed. However, achieving two actively powered rotations at different frequencies within a single molecule has remained elusive. Here molecular motors are presented incorporating two structurally distinct rotors, each operating at a unique rotational frequency-resembling a molecular steering system. The rotor activation preference arises from differences in photochemical, rather than thermal, behaviour and can be tuned by the rotor structure, solvent and light source. This discovery of controlling mixed rotor systems could, in principle, be applied to other rotors, combinations thereof and even to other classes of molecular motors, and thus could serve as a blueprint for the construction of future advanced synthetic molecular machines.