In the last decade, the aggregation-induced emission (AIE) and crystallization-induced emission (CIE) photophysical phenomena were observed in a series of non-emissive luminogens. Contrary to the "classical" behaviour of organic fluorophores, these molecules emit weakly or moderately in dilute solutions, in amorphous or disordered solids but become very efficiently emissive when aggregated in concentrated solutions or in crystalline states. Over the last years, a real effort has been made to understand and optimize the luminescent properties of AIEgen molecules and materials in order to use them in high-tech innovative devices such as light-emitting diode (OLED) or luminescent solar concentrators (LSC). To incorporate these fluorophores into such opto-electronic devices, luminescent molecules should be in assemblies into thin films, aggregates or polymer matrix. Controlling and optimizing the AIE phenomenon in these different complex environments thus represents a real challenge.Computational chemistry along with the wide range of molecular modelling techniques (from PCM-TD-DFT to Molecular Dynamics in solution or in a polymer matrix) is appropriate for the investigation of such phenomena.We propose here a full study of the optical properties of an organic molecule, namely the triphenylamine-substituted [(Z)-4-benzylidene-2-methyloxazol-5(4H)-one] (TPABMO), in solution, crystalline and aggregated phase and in a polybutadiene matrix. This molecule exhibits different behaviors depending of the considered environment, both the color of the emitted light and the efficiency of this emission process depending on the environment. For each phase, we propose a tailored computational protocol (see Figure 1) to rationalize the effect of the surrounding on the optical properties and the emission modulation. We show thatthe appropriate modeling of the environmental effects is crucial to predict the behavior of AIE/CIE candidates and to pave the way towards the development of novel CIE functional materials.

Modelling the aggregation-induced emission phenomena: Challenge for computational chemistry

2019 Fall National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.