2-(Benzothiazol-2-yl)pyren-1-ol (P3-NS) was developed as a excited-state intramolecular proton transfer (ESIPT)- based sensor for nitroaromatic compounds (NACs). Results of studies of its photophysical and optical properties show that P3-NS exists in various, solvent dependent isomeric forms arising from rotation about the CC bond connecting the benzothiazole and pyren-1-ol rings and the location of the pyrene-OH proton. The results of density functional theory (DFT) calculations enabled identification of the major structures of P3-NS dissolved in different solvents. Upon electronic excitation in nonpolar or weakly polar solvents, P3-NS undergoes an ESIPT reaction to form a product that only weakly fluoresces. In contrast, P3-NS exists in a strongly fluorescent deprotonated form in highly polar solvents. The results of time-dependent DFT calculations indicate that fluorescence quenching of the product generated by ESIPT reaction of P3-NS is caused by intersystem crossing at a conical intersection between S₁ and T₂ states. The anionic form of P3-NS, present in highly polar solvents, was shown to be a fluorescence sensor for nitroaromatic compounds (NACs). Fluorescence quenching by NACs occurs by protonation of the anionic form of P3-NS (static quenching) and by photoinduced electron transfer from the anionic form to NACs (dynamic quenching).

2-（Benzothiazol-2-yl）pyren-1-ol（P3-NS）被开发为基于激发态分子内质子转移（ESIPT）的硝基芳香族化合物（NAC）传感器。对它的光物理和光学性质的研究结果表明，P3-NS以各种溶剂依赖性异构体形式存在，这些异构体是围绕围绕苯并噻唑和and-1-醇环的C C键旋转以及the-OH质子的位置而产生的。密度泛函理论（DFT）计算的结果能够识别溶解在不同溶剂中的P3-NS的主要结构。在非极性或弱极性溶剂中电子激发时，P3-NS经历ESIPT反应形成仅微弱发荧光的产物。相反，P3-NS在强极性溶剂中以强荧光去质子化形式存在。随时间变化的DFT计算结果表明，由P3-NS的ESIPT反应生成的产物的荧光猝灭是由在S ₁和T ₂状态之间的圆锥形交叉处的系统间交叉引起的。存在于高极性溶剂中的P3-NS阴离子形式显示为硝基芳香族化合物（NAC）的荧光传感器。NAC的荧光猝灭是通过P3-NS阴离子形式的质子化而发生的 （静态猝灭）和通过光诱导电子从阴离子形式转移到NAC（动态猝灭）。