Liu Yan-Ling, Wang Wenji, Yu Huixin, Yuan Mao-Sen
Department of Chemistry & Chemical Engineering, Lvliang University, Lishi 033000, PR China.
College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2025 Jan 15;325:125139. doi: 10.1016/j.saa.2024.125139. Epub 2024 Sep 14.
Multi-branched π-conjugated organic molecules, due to their fascinating structures and unique optical properties, exhibit potential applications in optoelectronics. Herein, series of 4-N,N-diphenylaminostyryl substituted multi-branched truxene compounds (namely TN1, TN2 and TN3) and a truxene-triindole compound (namely N3T3) were synthesized. These compounds are characterized by effective π-extension and remarkably enhanced two-photon absorption (TPA) compared to their less π-conjugated analogues. For truxene compounds, the more the number of the branch, the large the TPA efficiency, and the C-symmetric three-branched TN3 exhibit the largest TPA. The aromatic triindole unit proves to be a better two-photon fluorophore compared with truxene. The results conclude that the influence of π-conjugation, molecular planarity and intramolecular charge-transfer (ICT) to TPA is far more pronounced than to linear optical properties.
多支链π共轭有机分子因其迷人的结构和独特的光学性质，在光电子学领域展现出潜在应用。在此，合成了一系列4-N，N-二苯胺基苯乙烯基取代的多支链并四苯化合物（即TN1、TN2和TN3）以及一种并四苯-三吲哚化合物（即N3T3）。与π共轭程度较低的类似物相比，这些化合物具有有效的π扩展和显著增强的双光子吸收（TPA）特性。对于并四苯化合物，支链数量越多，TPA效率越高，且具有C对称性的三分支TN3表现出最大的TPA。与并四苯相比，芳香族三吲哚单元被证明是更好的双光子荧光团。结果表明，π共轭、分子平面性和分子内电荷转移（ICT）对TPA的影响比对线性光学性质更为显著。
