Blue-to-Green Delayed Fluorescence of 2-Aminoisophthalic Acid Diesters Dispersed in Polymer Film
作者:Masaki Shimizu、Masaki Nakatani
DOI:10.1002/ejoc.201700695
日期:2017.9.1
very small, which allows reverse intersystem crossing leading to delayed fluorescence emission. Indeed, the diesters dispersed in poly(methyl methacrylate) (PMMA) films exhibit luminescence consisting of two components, the lifetimes of which are in the order of nano- and microseconds, respectively. The luminescence spectra of the PMMA films in air completely overlap with those recorded under vacuum, which
我们已经从市售的2-溴间苯二甲酸二甲酯合成了十个2-氨基间苯二甲酸二酯。在室温下,发现2-甲基四氢呋喃中的二酯为非发射性或微弱的荧光(Φ = 0.04-0.08),而其粉末形式的每种酯在蓝色至绿色光谱区域均显示荧光,其发光效率优于在解决方案中。DFT计算表明,发光是由分子内电荷从氨基部分转移至间苯二甲酸酯核所产生的最低单线态激发态产生的。与时间有关的DFT计算表明,S 1和T 1之间的能隙态非常小,这使得反向的系统间交叉导致延迟的荧光发射。实际上,分散在聚(甲基丙烯酸甲酯)(PMMA)膜中的二酯显示出由两种组分组成的发光,其寿命分别在纳秒和微秒的数量级。空气中PMMA膜的发光光谱与真空下记录的光谱完全重叠,这表明可以将长寿命的发射归因于延迟的荧光。