Light‐ and Heat‐Induced Reversal of Circularly Polarized Luminescence in a Single Molecule

Abstract Switching the handedness of circularly polarized luminescence (CPL) at the molecular level remains a challenge in the development of responsive chiral materials. We report a light‐driven molecular motor covalently linked to two perylenediimide (PDI) chromophores, enabling reversible and directional modulation of CPL. The different motor states, which are accessible in a unidirectional fashion via light‐irradiation and thermal helix inversion steps, respectively, display significantly distinct chiroptical properties. In addition, our system allows switching of the chiral induction process and hence, the observation of a CPL signal. The present work discloses the first example of reversible CPL sign inversion triggered by light irradiation at the single molecular level, offering a new starting point for designing emitters with light‐responsive chirality modulation.