Jiawei Li, Cheng Chen*, Mingyan Wu*
Chin. J. Struct. Chem., 2025, 44(3), 100513. DOI: 10.1016/j.cjsc.2025.100513
March 1, 2025
ABSTRACT
In summary, we have employed the planar achiral Py molecule and chiral naphthalenediimide-based triangular macrocycle R-NDI as donor and acceptor to synthesize organic cocrystals R-NDI-Py and S-NDI-Py through outer-surface π-π interactions. The supramolecular donor-acceptor co-assembly approach and the consiquent intermolecular CT interactions inherited and improved the circular polarized luminescence activity of R-NDI and S-NDI precursors, endowing R-NDI-Py and S-NDI-Py a rare deep-red and NIR emission at 672 nm with the maximum luminescent asymmetric g factor (glum) of -1.4 * 10-2 and +1.3 * 10-2. It also promoted the TPA property of R-NDI-Py and S-NDI-Py, resulting in a deep-red and NIR emission centered on 680 nm, with a 184 nm red-shift compared with R-NDI and S-NDI precursors, and the TPA cross-section at 810 nm can be calculated up to 2.277 * 103 GM. The fluorescence, CPL and TPA experiments, crystal structure analysis and theoretical calculation demonstrate the adjustability of the packing mode in the D–A self-assembly system, thereby offering an effective strategy for designing and synthesizing multi-functional crystalline optical materials.