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Vibronic and vibrational coherences in two-dimensional electronic spectra of supramolecular J-aggregates.

ABSTRACT: In J-aggregates of cyanine dyes, closely packed molecules form mesoscopic tubes with nanometer-diameter and micrometer-length. Their efficient energy transfer pathways make them suitable candidates for artificial light harvesting systems. This great potential calls for an in-depth spectroscopic analysis of the underlying energy deactivation network and coherence dynamics. We use two-dimensional electronic spectroscopy with sub-10 fs laser pulses in combination with two-dimensional decay-associated spectra analysis to describe the population flow within the aggregate. Based on the analysis of Fourier-transform amplitude maps, we distinguish between vibrational or vibronic coherence dynamics as the origin of pronounced oscillations in our two-dimensional electronic spectra.

SUBMITTER: Milota F

PROVIDER: S-EPMC3725611 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Vibronic and vibrational coherences in two-dimensional electronic spectra of supramolecular J-aggregates.

Milota Franz F Prokhorenko Valentyn I VI Mancal Tomas T von Berlepsch Hans H Bixner Oliver O Kauffmann Harald F HF Hauer Jürgen J

The journal of physical chemistry. A 20130318 29

In J-aggregates of cyanine dyes, closely packed molecules form mesoscopic tubes with nanometer-diameter and micrometer-length. Their efficient energy transfer pathways make them suitable candidates for artificial light harvesting systems. This great potential calls for an in-depth spectroscopic analysis of the underlying energy deactivation network and coherence dynamics. We use two-dimensional electronic spectroscopy with sub-10 fs laser pulses in combination with two-dimensional decay-associat ...[more]

PMID: 23461650

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