State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Street, Changchun (P. R. China).
Angew Chem Int Ed Engl. 2015 Jul 13;54(29):8369-73. doi: 10.1002/anie.201503914. Epub 2015 Jun 3.
A series of highly efficient deep red to near-infrared (NIR) emissive organic crystals 1-3 based on the structurally simple 2'-hydroxychalcone derivatives were synthesized through a simple one-step condensation reaction. Crystal 1 displays the highest quantum yield (Φf) of 0.32 among the reported organic single crystals with an emission maximum (λem) over 710 nm. Comparison between the bright emissive crystals 1-3 and the nearly nonluminous compounds 4-7 clearly gives evidence that a subtle structure modification can arouse great property changes, which is instructive in designing new high-efficiency organic luminescent materials. Notably, crystals 1-3 exhibit amplified spontaneous emissions (ASE) with extremely low thresholds. Thus, organic deep red to NIR emissive crystals with very high Φf have been obtained and are found to display the first example of NIR fluorescent crystal ASE.
一系列基于结构简单的 2'-羟基查耳酮衍生物的高效深红光至近红外（NIR）发射有机晶体 1-3 通过简单的一步缩合反应合成。晶体 1 的量子产率（Φf）高达 0.32，在报道的具有超过 710nm 的发射最大值（λem）的有机单晶中最高。明亮发射晶体 1-3 与几乎无光的化合物 4-7 之间的比较清楚地证明了细微的结构修饰可以引起巨大的性质变化，这对设计新的高效有机发光材料具有指导意义。值得注意的是，晶体 1-3 表现出极低阈值的放大自发发射（ASE）。因此，获得了具有非常高Φf的有机深红光至 NIR 发射晶体，并发现它们显示了 NIR 荧光晶体 ASE 的第一个实例。
