title: The electronically excited states of LH2 complexes from Rhodopseudomonas acidophila strain 10050 studied by time-resolved spectroscopy and dynamic Monte Carlo simulations. I. Isolated, non-interacting LH2 complexes.
abstract: We have employed time-resolved spectroscopy on the picosecond time scale in combination with dynamic Monte Carlo simulations to investigate the photophysical properties of light-harvesting 2 (LH2) complexes from the purple photosynthetic bacterium Rhodopseudomonas acidophila. The variations of the fluorescence transients were studied as a function of the excitation fluence, the repetition rate of the excitation and the sample preparation conditions. Here we present the results obtained on detergent solubilized LH2 complexes, i.e., avoiding intercomplex interactions, and show that a simple four-state model is sufficient to grasp the experimental observations quantitatively without the need for any free parameters. This approach allows us to obtain a quantitative measure for the singlet-triplet annihilation rate in isolated, noninteracting LH2 complexes.
authors.affiliation: Experimental Physics IV and BIMF, University of Bayreuth, D-95440 Bayreuth, Germany.
authors.forename: Tobias J
authors.initials: TJ
authors.lastname: Pflock
authors.forename: Silke
authors.initials: S
authors.lastname: Oellerich
authors.forename: June
authors.initials: J
authors.lastname: Southall
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Cogdell
authors.forename: G Matthias
authors.initials: GM
authors.lastname: Ullmann
authors.forename: Jürgen
authors.initials: J
authors.lastname: Köhler
mesh_terms: D003198:Computer Simulation; D003902:Detergents / Q000737:chemistry; D045342:Light-Harvesting Protein Complexes / Q000737:chemistry*; D008954:Models, Biological; D009010:Monte Carlo Method; D012241:Rhodopseudomonas / Q000737:chemistry*; D012995:Solubility; D013057:Spectrum Analysis
chemical_list: D003902:Detergents; D045342:Light-Harvesting Protein Complexes