Modulation of circularly polarized luminescence through excited-state symmetry breaking and interbranched exciton coupling in helical push-pull organic systems

Kais Dhbaibi (1, 2) , Ludovic Favereau (1, 3) , Monika Srebro-Hooper (4) , Cassandre Quinton (1, 3) , Nicolas Vanthuyne (5) , Lorenzo Arrico (6) , Thierry Roisnel (1, 3) , Bassem Jamoussi (7) , Cyril Poriel (1, 3) , Clément Cabanetos (8) , Jochen Autschbach (9) , Jeanne Crassous (1, 3)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 University of Gabes
3 ScanMAT - Synthèse Caractérisation Analyse de la Matière
4 UJ - Uniwersytet Jagielloński w Krakowie = Jagiellonian University
5 ISM2 - Institut des Sciences Moléculaires de Marseille
6 University of Pisa - Università di Pisa
7 King Abdulaziz University
8 MOLTECH-Anjou
9 Department of Chemistry [Buffalo]

pi-Helical push-pull dyes were prepared and their (chir)optical properties were investigated both experimentally and computationally. Specific fluorescent behaviour of bis-substituted system was observed with unprecedented solvent effect on the intensity of circularly polarized luminescence (CPL, dissymmetry factor decreasing from 10(-2) to 10(-3) with an increase in solvent polarity) that was linked to a change in symmetry of chiral excited state and suppression of interbranched exciton coupling. The results highlight the potential of CPL spectroscopy to study and provide a deeper understanding of electronic photophysical processes in chiral pi-conjugated molecules.

Domaines: Chimie théorique et/ou physique; Chimie organique

Kais Dhbaibi, Ludovic Favereau, Monika Srebro-Hooper, Cassandre Quinton, Nicolas Vanthuyne, et al.. Modulation of circularly polarized luminescence through excited-state symmetry breaking and interbranched exciton coupling in helical push-pull organic systems. Chemical Science, 2020, 11 (2), pp.567-576. ⟨10.1039/c9sc05231c⟩. ⟨hal-02470140⟩