Ultrabroadband two-dimensional electronic spectroscopy reveals energy flow pathways in LHCII across the visible spectrum

Abstract

We utilise ultrabroadband two-dimensional electronic spectroscopy to map out pathways of energy flow in LHCII across the entire visible region. In addition to the well-established, low-lying chlorophyll Qy bands, our results reveal additional pathways of energy relaxation on the higher-lying excited states involving the S2 energy levels of carotenoids, including ultrafast carotenoid-to-chlorophyll energy transfer on 90-150 fs timescales.

Plant carotenoids: recent advances and future perspectives

“…With the quantum chemical evaluation, the carotenoid to chlorophyll energy transfer was found to be coherent rather than loose interaction (Ghosh et al 2017;Meneghin et al 2018). The lutein molecules in LHCII have been identified as key chromophores for the control of the excitation energy flow (Son et al 2019). These studies point a central role of carotenoids rather than accessory function in light harvesting.…”