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Interplay Between J- and H-Type Coupling in Aggregates of ?-Conjugated Polymers: A Single-Molecule Perspective.

ABSTRACT: Strong dipole-dipole coupling within and between ?-conjugated segments shifts electronic transitions, and modifies vibronic coupling and excited-state lifetimes. Since J-type coupling between monomers along the conjugated-polymer (CP) chain and H-type coupling of chromophores between chains of a CP compete, a superposition of the spectral modifications arising from each type of coupling emerges, making the two couplings hard to discern in the ensemble. We introduce a single-molecule H-type aggregate of fixed spacing and variable length of up to 10?nm. HJ-type aggregate formation is visualized intuitively in the scatter of single-molecule spectra.

SUBMITTER: Eder T

PROVIDER: S-EPMC6973276 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Interplay Between J- and H-Type Coupling in Aggregates of π-Conjugated Polymers: A Single-Molecule Perspective.

Eder Theresa T Vogelsang Jan J Bange Sebastian S Remmerssen Klaas K Schmitz Daniela D Jester Stefan-S SS Keller Tristan J TJ Höger Sigurd S Lupton John M JM

Angewandte Chemie (International ed. in English) 20191106 52

Strong dipole-dipole coupling within and between π-conjugated segments shifts electronic transitions, and modifies vibronic coupling and excited-state lifetimes. Since J-type coupling between monomers along the conjugated-polymer (CP) chain and H-type coupling of chromophores between chains of a CP compete, a superposition of the spectral modifications arising from each type of coupling emerges, making the two couplings hard to discern in the ensemble. We introduce a single-molecule H-type aggre ...[more]

PMID: 31596527

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