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arXiv · 1311.3068

Distinguishing electronic and vibronic coherence in 2D spectra by their temperature dependence

Václav Perlík·Craig Lincoln·František Šanda·Jürgen Hauer
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Abstract

Long-lived oscillations in 2D spectra of chlorophylls are at the heart of an ongoing debate. Their physical origin is either a multi-pigment effect, such as excitonic coherence, or primarily stems from localized vibrations. In the present work, we analyze distinguishing characteristics of relative phase difference measured between diagonal- and cross-peak oscillations. While direct discrimination between the two scenarios is obscured when peaks overlap, their sensitivity to temperature provides a stronger argument. We show that vibrational (vibronic) oscillations change relative phase with temperature, while electronic oscillations are only weakly dependent. This highlights that studies of relative phase difference as a function of temperature provide a clear and easily accessible method to distinguish between vibrational and electronic coherences.

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Václav Perlík, Craig Lincoln, František Šanda, Jürgen Hauer. 2013-11-13. Distinguishing electronic and vibronic coherence in 2D spectra by their temperature dependence. https://doi.org/10.1021/jz402468c

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