Thermally Assisted Photonic Inversion of Supramolecular Handedness

摘要

Symmetry breaking, leading to a specific handedness (either right or left) of biological structures is one of the most fascinating phenomenon in nature. Notably, nature is able to translate molecular chirality into supramolecular handedness, through genetic-information transfer, thereby creating functionally incredible helical structures of nanoscopic and macroscopic dimensions, including giant superstructures. While several factors such as vortex motion, stirring, magnetic field,and redox forces may be involved, natural light may have a key role in controlling the chirality and helical sense of biological helices. Light is undoubtedly a versatile external stimulus to control the chemical and physical properties of molecules, both natural and synthetic. Chirality is one of the chemical properties that can be manipulated using light. For example, photoisomerization of azobenzene' has been used as a trigger to induce point chirality on a molecular level, whereas on a macromolecular level, light is known to influence the helicity of polymers and self-assemblies. While molecular chirality and single-chain polymer helicity are easy to manipulate with circularly polarized light, reversible control of supramolecular helicity in a macroscopic self-assembly using unpolarized light is challenging.