Shifting the twist of organic microribbons by external stimulus

Soft materials with morphological changes in response to external stimuli attract intensive interest because of their applications in actuators and sensors. Speed of response, one of the most important parameters, is related to the active components and the elasticity. Here, using predictive design principles, we report a class of layered microribbons exhibited fast electro-induced response. By increasing the length of the side chains of perylene diimides to tune the elastic modulus, we find that twisting rate is inversely proportional to elasticity modulus. Twisting arises from screw dislocations of the monomers by diagonal π-stacking distortion relative to the microribbon axis. Our work offers principles applicable to designing other layered molecular systems when the goal is rapid response to external stimuli.