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

ABSTRACT: ?-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 ?-conjugated molecules.

SUBMITTER: Dhbaibi K

PROVIDER: S-EPMC7069512 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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

Dhbaibi Kais K Favereau Ludovic L Srebro-Hooper Monika M Quinton Cassandre C Vanthuyne Nicolas N Arrico Lorenzo L Roisnel Thierry T Jamoussi Bassem B Poriel Cyril C Cabanetos Clément C Autschbach Jochen J Crassous Jeanne J

Chemical science 20191120 2

π-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 interbranche ...[more]

PMID: 32206274

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