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Title: Modulation of circularly polarized luminescence through excited-state symmetry breaking and interbranched exciton coupling in helical push–pull organic systems
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 interbranched exciton coupling. The results highlight the potential of CPL spectroscopy to study and provide a deeper understanding of electronic photophysical processes in chiral π-conjugated molecules.
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Journal Name:
Chemical Science
Page Range or eLocation-ID:
567 to 576
Sponsoring Org:
National Science Foundation
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