Boosting Circularly Polarized Luminescence of Organic Conjugated Systems Twisted Intramolecular Charge Transfer.

Realizing a high luminescence dissymmetry factor ( ) is a paramount yet challenging issue in the research field of circularly polarized luminescence (CPL). Here, we reported a novel set of organic conjugated systems with twisted intramolecular charge transfer (TICT) characteristics based on conjugated -carborane-binaphthyl dyads composing of binaphthyl units as chiral electron donors and -carborane units as achiral electron acceptors, demonstrating intense CPL with large values. Interestingly, single-crystalline -1 exhibited a high-level brightness and a large factor as high as +0.13, whereas single-crystalline -2 processed a relatively low brightness with a decreased value to -0.04. The significant diversity of CPL-active properties was triggered by the selective introduction of -carborane units onto the binaphthyl units. Benefiting from the large magnetic dipole transition moments in TICT states, the CPL activity of TICT -carborane-based materials exhibited amplified circular polarization. This study provides an efficient molecular engineering strategy for the rational design and development of highly efficient CPL-active materials.