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arXiv · 1210.6665

Two-Dimensional Electronic Spectroscopy Using Incoherent Light: Theoretical Analysis

Daniel B. Turner·Dylan J. Howey·Erika J. Sutor·Rebecca A. Hendrickson·M. W. Gealy·Darin J. Ulness
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Abstract

Electronic energy transfer in photosynthesis occurs over a range of time scales and under a variety of intermolecular coupling conditions. Recent work has shown that electronic coupling between chromophores can lead to coherent oscillations in two-dimensional electronic spectroscopy measurements of pigment-protein complexes measured with femtosecond laser pulses. A persistent issue in the field is to reconcile the results of measurements performed using femtosecond laser pulses with physiological illumination conditions. Noisy-light spectroscopy can begin to address this question. In this work we present the theoretical analysis of incoherent two-dimensional electronic spectroscopy, I(4) 2D ES. Simulations reveal diagonal peaks, cross peaks, and coherent oscillations similar to those observed in femtosecond two-dimensional electronic spectroscopy experiments. The results also expose fundamental differences between the femtosecond-pulse and noisy-light techniques; the differences lead to new challenges and new opportunities.

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Daniel B. Turner, Dylan J. Howey, Erika J. Sutor, Rebecca A. Hendrickson, M. W. Gealy, Darin J. Ulness. 2012-12-06. Two-Dimensional Electronic Spectroscopy Using Incoherent Light: Theoretical Analysis. https://doi.org/10.1021/jp310477y

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