Generation of efficient Dual Emitters based on 6-membered ring Excited State Intramolecular Proton Transfer (ESIPT) molecular systems. – GeDEmi

The GeDEmi project is devoted to the rationalization and optimization of molecules presenting a dual emission based on the Excited State Intramolecular Proton Transfer mechanism. These fluorescent molecules present a strong H-bond and, after photon absorption, a prototropy occurs from the excited enol (E) to form the excited Keto (K) isomer. The selected backbones are anticipated to present large quantum yields in both solution and solid-state. Through a joint design by the two partners (based on chemical feasibility and the results of accurate quantum modeling), fluorophores with E and K excited states presenting almost the same energy will be synthesized. There are fundamental challenges in this project: on the one hand, the rational design of sophisticated luminophores with the help of ab initio calculations, and, on the other hand, the rapid synthetic implementation to ascertain the optical properties. The dual emission and more precisely the intensity ratio of the two emission bands can be perturbed by external stimuli, opening the way to development of new ratiometric fluorescent probes, the electronic interactions between an analyte and the molecular core bringing variations of the relative peaks intensity. Such probes are of great interest for the determination of pollutants in water or in cellulo to help understanding of biological phenomena or pathology detection (by tracking and quantification of ions or metabolites). In addition, the efficient luminescence of this family of compounds in the solid state renders them good candidates for incorporation in luminescent devices supported fluorescent probes or for use in safety inks formulations with unique signature