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Insights into the origins of inverted circular dichroism in thin films of a chiral side chain polyfluorene.

ABSTRACT: We synthesized a fluorene-bithiophene co-polymer with chiral side chains (cPFT2) and investigated its chiroptical properties via synchotronradiation circular dichroism. We observed that thin films of the polymer display an intense circular dichroism (CD) upon annealing, which is of opposite handedness to the CD reported for similar polyfluorenes bearing the same enantiomeric chiral side chain. We then contrast the properties of this polymer with chiral side chain fluorene homopolymer (cPF) and observe large differences in their thin film morphology. Using photoluminescence spectroscopy, we uncover evidence of polymer chain bending in cPFT2, which is further supported by theoretical calculations, and propose an explanation for the observed inverted optical activity.

SUBMITTER: Minion L

PROVIDER: S-EPMC10946986 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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Insights into the origins of inverted circular dichroism in thin films of a chiral side chain polyfluorene.

Minion Louis L Wade Jessica J Moreno-Naranjo Juan Manuel JM Ryan Seán S Siligardi Giuliano G Fuchter Matthew J MJ

Chirality 20230622 11

We synthesized a fluorene-bithiophene co-polymer with chiral side chains (cPFT2) and investigated its chiroptical properties via synchotronradiation circular dichroism. We observed that thin films of the polymer display an intense circular dichroism (CD) upon annealing, which is of opposite handedness to the CD reported for similar polyfluorenes bearing the same enantiomeric chiral side chain. We then contrast the properties of this polymer with chiral side chain fluorene homopolymer (cPF) and o ...[more]

PMID: 37349263

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