CircularlyPolarized Light-Regulable Crystal–LiquidPhase Transition of Self-Assembled Macroscopic Chiral Twisted Ribbons

Chirality is a fundamental property of nature, observed at the subatomic, molecular, supramolecular, and macroscopic levels. Circularly polarized light (CPL) has attracted extensive attention as an effective tool for regulating and inducing chirality on various scales. Herein, we report the formation of micron-scale twisted ribbons from homochiral molecular H₈-BAz through self-assembly driven by solvophobic interactions. The chiral information in H₈-BAz is effectively transferred and amplified in the supramolecular structure and finally appears as macroscopic homochiral twisted ribbons that match the chirality of the monomers. The ribbons undergo a photoinduced crystal-to-liquid transition (PCLT) when exposed to 365 nm light due to the isomerization of the azobenzene structure. Additionally, the PCLT behavior of chiral ribbons is regulated by CPL: When irradiated with homochiral right-handed CPL (RCP), the ribbon with a <i>P</i>-helix formed by (<i>R</i>)-H₈-BAz undergoes a faster phase transition. The <i>M</i>-helix ribbon undergoes a faster phase transition with left-handed CPL (LCP). The average time difference for the phase transition reaches 1.5 times. Our results demonstrate a simple method for creating macroscopic chiral structures and the impact of chiral light sources on their phase transition process.