Efficient and accurate simulations of two-dimensional electronic photon-echo signals: Illustration for a simple model of the Fenna-Matthews-Olson complex

Journal Article · Thu Jan 07 04:00:00 EST 2010 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.3268705· OSTI ID:21559870

Sharp, Leah Z; Egorova, Dassia; Domcke, Wolfgang ^[1]

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1. Department of Chemistry, Technische Universitaet Muenchen, D-85747 Garching (Germany)

Two-dimensional (2D) photon-echo spectra of a single subunit of the Fenna-Matthews-Olson (FMO) bacteriochlorophyll trimer of Chlorobium tepidum are simulated, employing the equation-of-motion phase-matching approach (EOM-PMA). We consider a slightly extended version of the previously proposed Frenkel exciton model, which explicitly accounts for exciton coherences in the secular approximation. The study is motivated by a recent experiment reporting long-lived coherent oscillations in 2D transients [Engel et al., Nature 446, 782 (2007)] and aims primarily at accurate simulations of the spectroscopic signals, with the focus on oscillations of 2D peak intensities with population time. The EOM-PMA accurately accounts for finite pulse durations as well as pulse-overlap effects and does not invoke approximations apart from the weak-field limit for a given material system. The population relaxation parameters of the exciton model are taken from the literature. The effects of various dephasing mechanisms on coherence lifetimes are thoroughly studied. It is found that the experimentally detected multiple frequencies in peak oscillations cannot be reproduced by the employed FMO model, which calls for the development of a more sophisticated exciton model of the FMO complex.

• OSTI ID: 21559870
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 1 Vol. 132; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
APPROXIMATIONS
BOSONS
CALCULATION METHODS
CHEMICAL REACTIONS
COMPLEXES
DIFFERENTIAL EQUATIONS
ELEMENTARY PARTICLES
EQUATIONS
EQUATIONS OF MOTION
EXCITON MODEL
EXCITONS
MASSLESS PARTICLES
MATHEMATICAL MODELS
MICROORGANISMS
NUCLEAR MODELS
OSCILLATIONS
PARTIAL DIFFERENTIAL EQUATIONS
PEAKS
PHOTOCHEMICAL REACTIONS
PHOTONS
PHOTOSYNTHESIS
POPULATIONS
PULSES
QUASI PARTICLES
RELAXATION
SIGNALS
SIMULATION
SPECTRA
SYNTHESIS
TWO-DIMENSIONAL CALCULATIONS