Excited photophysics of a synthesized molecule namely 2-(benzo[d]thiazol-2-yl)-5-nitrophenol (BTNP) have been studied using steady state and time resolved techniques. BTNP exhibits ESIPT exclusively in non-polar media with exceptional Stokes’ shift. In polar solvents anion formation of BTNP hampers the ESIPT process. Solid state emission spectral pattern matches reasonably well with that in non-polar medium. Dynamic light scattering showed the increment of particle size in heptane in comparison to water, a trend reversed to conventional trait of Aggregation Induced Emission (AIE) active molecules. Nitro substituent in BTNP reverses the conventional definition of a ‘good solvent’ and ‘bad solvent’, thereby promoting ESIPT in non-polar medium via aggregation. As all reports on AIE active compounds claim water to be the solvent capable of producing the effect, we have reversed the effect by simple change in substitution. Reversal of AIE phenomenon would certainly open up new avenues in future research on AIE active fluorophores.

已经使用稳态和时间分辨技术研究了合成分子2-（苯并[ d ]噻唑-2-基）-5-硝基苯酚（BTNP）的激发光物理。BTNP专门在非极性媒体中展示ESIPT，并具有出色的斯托克斯位移。在极性溶剂中，BTNP的阴离子形成会阻碍ESIPT过程。固态发射光谱图与非极性介质中的光谱图合理匹配。动态光散射显示与水相比，庚烷中粒径增加，这种趋势与聚集诱导发射（AIE）活性分子的常规特性相反。BTNP中的硝基取代基颠倒了“良溶剂”和“不良溶剂”的常规定义，从而通过聚集促进了非极性介质中的ESIPT。由于所有有关AIE活性化合物的报道都声称水是能够产生这种作用的溶剂，因此我们通过简单地改变取代作用就扭转了这种作用。AIE现象的逆转必将为AIE活性荧光团的未来研究开辟新的途径。