title: Role of coherent vibrations in energy transfer and conversion in photosynthetic pigment-protein complexes.
abstract: Oscillatory features of two-dimensional spectra of photosynthetic pigment-protein complexes during few picoseconds after electronic excitations of chlorophylls in various pigment-proteins were recently related to the coherent nuclear vibrations. It has been also speculated that the vibrations may assist the excitonic energy transfer and charge separation, hence contributing to energy transport and energy conversion efficiency. Here, we consider three theoretical approaches usually used for characterization of the excitation dynamics and charge separation, namely Redfield, Förster, and Marcus model descriptions, regarding this question. We show that two out of the three mechanisms require explicit resonances of excitonic splittings and the nuclear vibration frequencies. However, the third one related to the electron transfer is in principle off resonant.
authors.affiliation: Department of Theoretical Physics, Vilnius University, Sauletekio al. 9-III, 10222, Vilnius, Lithuania. darius.abramavicius@ff.vu.lt.
authors.forename: Darius
authors.initials: D
authors.lastname: Abramavicius
authors.affiliation: Department of Theoretical Physics, Vilnius University, Sauletekio al. 9-III, 10222, Vilnius, Lithuania. leonas.valkunas@ff.vu.lt.|Center for Physical Sciences and Technology, A. Gostauto 11, 01108, Vilnius, Lithuania. leonas.valkunas@ff.vu.lt.
authors.forename: Leonas
authors.initials: L
authors.lastname: Valkunas
mesh_terms: D002734:Chlorophyll / Q000737:chemistry / Q000378:metabolism; D004735:Energy Transfer; D008954:Models, Biological; D008962:Models, Theoretical; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry* / Q000378:metabolism*; D014732:Vibration
chemical_list: D045322:Photosynthetic Reaction Center Complex Proteins; D002734:Chlorophyll
keywords: Electron transfer; Electronic coherence; Energy transfer; Vibrational coherence