Two-dimensional electronic spectra of the photosynthetic apparatus of green sulfur bacteria

Abstract

Advances in time resolved spectroscopy have provided new insight into the energy transmission in natural photosynthetic complexes. Novel theoretical tools and models are being developed in order to explain the experimental results. We provide a model calculation for the two-dimensional electronic spectra of Cholorobaculum tepidum which correctly describes the main features and transfer time scales found in recent experiments. From our calculation one can infer the coupling of the antenna chlorosome with the environment and the coupling between the chlorosome and the Fenna-Matthews-Olson complex. We show that environment assisted transport between the subunits is the required mechanism to reproduce the experimental two-dimensional electronic spectra.

Effect of disorder and polarization sequences on two-dimensional spectra of light-harvesting complexes

“…The reorganization energy leads to a downward shift of the diagonal and cross peaks with increasing delay Kramer and Rodriguez 2017). The observed shift is consistent with the organization energies around 40/cm assigned by (Adolphs and Renger 2006) to the bacteriochlorophylls contained in the FMO complex.…”

“…For the FMO complex contained in green sulfur bacteria (Olson and a Romano 1962;Fenna and Matthews 1975;Blankenship 2014), the transfer dynamics mirrored in 2DES has been analyzed with HEOM by Chen et al (2011);Hein et al (2012); Kreisbeck and Kramer (2012). In contrast to the SE/ESA contributions, the ground state bleaching (GSB) pathway mirrors the linear absorption signal at long delay times and does not provide direct insights into the population dynamics (Kramer and Rodriguez 2017). However, GSB is particularly susceptible to vibrational motion, which enters the 2DES (Tiwari et al 2013;Kreisbeck et al 2013) and produces beating signals in the cross-peak amplitudes as function of the delay time T 2 .…”

Scattering theory of efficient quantum transport across finite networks

“…Shown are three different values of the width of the distribution of energy shifts, relative to the input-output coupling,σ = σ/2V . The parameters0 = s0/2V is set to zero, which is consistent with the dominant doublet condition (9,32). Figure obtained from [35].…”

Efficient calculation of open quantum system dynamics and time‐resolved spectroscopy with distributed memory HEOM (DM‐HEOM)

“…The relative contributions of stimulated emission, ground state bleaching and excited state absorption, as well as the relationship between 2D spectra and transient absorption spectra is analyzed in Ref. for an enlarged model of the FMO complex. The energy transfer and relaxation toward lower lying states is directly reflected in the stimulated emission signal.…”