Coordination-driven stacking of carbazole-based molecule for dynamic long-lived room temperature phosphorescence

Distinguishing from static room temperature phosphorescence (RTP) materials, time-evolution dynamic RTP still face great challenges. In this work, we obtained two supramolecular coordination polymers [Cd2(CzIP)2(2-MIM)2] (1) and [Zn2(CzIP)4(DMI)2] (2) (CzIP = 5-(carbazol-9-yl) isophthalate, 2-MIM = 2-methylimidazole, DMI = N, N-Dimethylacetamide). These two compounds have the similar H-aggregation of carbazole fragments but with different overlap degree, but exhibit the different optical performance in phosphorescence lifetimes and stimuli responsive properties. The lifetimes of compounds 1 and 2 is 700.31 and 18.68 ms, respectively. Surprisingly, compound 1 exhibits dynamic room temperature phosphorescence with the color change from orange to green over the while delayed time. These results demonstrates that the coordination-tunable stacking behaviors play an important role in the generation of room temperature phosphorescence.