Aspect ratio-dependent twisting motions in photomechanical molecular crystal ribbons via solid-state [2+2] photodimerization

Abstract

Dynamic single-crystal ribbons based on a photoactive divinylphenyl derivative (MCPD) exhibit aspect ratio (δ, defined as length-to-width ratio)-dependent twisting motions under visible light irradiation. This crystal twisting is driven by solid-state [2+2] photodimerization, which can enable a single-crystal-to-single-crystal (SCSC) transformation in high-aspect-ratio ribbons and generate single crystals of the photodimer.