Li Chencheng, Zhao Jiang
School of Chemistry and Chemical Engineering, Guizhou University, Guiyang 550025, Guizhou, China.
Inorg Chem. 2024 Jun 24;63(25):11757-11767. doi: 10.1021/acs.inorgchem.4c01357. Epub 2024 Jun 12.
Emitters produce weak emissions when they undergo structural changes such as molecular configuration transformation (MCT) or excited-state intramolecular proton transfer (ESIPT) but give out strong emissions after terminating these distortions. Herein, an organoplatinum complex, , carrying a salicylaldehyde-based Schiff base unit is synthesized. It exhibits weak emission in dilute solutions but shows bright emission at the aggregated state or after interacting with F and Zn. This suggests that it has an aggregation-enhanced emission (AEE) property and holds potential in ion detection. Supported by theoretical calculations and femtosecond transient absorption results, this complex suffers excited-state structural changes including MCT from a square-planar configuration to a tetrahedral one, as well as intramolecular rotation of a monodentate ligand and ESIPT, showing weak emission in its solutions. At the aggregated state, it releases strong yellow emissions because of the restraints of MCT and ligand rotation. Upon interacting with F or Zn, it emits bright-red or -green emissions, achieving detection limits of 10 M. The sensing mechanism is concluded as deprotonation- and coordination-induced ESIPT terminations, respectively. Given its AEE property and ion-responsive emissions, its application in information encryption is also explored. Finally, these findings should provide valuable clues for the developments of chemosensors with dual-channel recognition abilities.
当发射体经历诸如分子构型转变(MCT)或激发态分子内质子转移(ESIPT)等结构变化时,会产生微弱的发射,但在这些畸变终止后会发出强烈的发射。在此,合成了一种带有水杨醛基席夫碱单元的有机铂配合物 。它在稀溶液中表现出微弱的发射,但在聚集态或与F和Zn相互作用后显示出明亮的发射。这表明它具有聚集增强发射(AEE)特性,在离子检测方面具有潜力。在理论计算和飞秒瞬态吸收结果的支持下,该配合物经历激发态结构变化,包括从平面正方形构型到四面体构型的MCT,以及单齿配体的分子内旋转和ESIPT,在其溶液中表现出微弱的发射。在聚集态,由于MCT和配体旋转的限制,它释放出强烈的黄色发射。与F或Zn相互作用时,它发出亮红色或绿色发射,检测限达到10 M。传感机制分别归结为去质子化和配位诱导的ESIPT终止。鉴于其AEE特性和离子响应发射,还探索了其在信息加密中的应用。最后,这些发现应为具有双通道识别能力的化学传感器的开发提供有价值的线索。