title: Coherence and population dynamics of chlorophyll excitations in FCP complex: Two-dimensional spectroscopy study.
abstract: Energy transfer processes and coherent phenomena in the fucoxanthin-chlorophyll protein complex, which is responsible for the light harvesting function in marine algae diatoms, were investigated at 77 K by using two-dimensional electronic spectroscopy. Experiments performed on femtosecond and picosecond timescales led to separation of spectral dynamics, witnessing evolutions of coherence and population states of the system in the spectral region of Qy transitions of chlorophylls a and c. Analysis of the coherence dynamics allowed us to identify chlorophyll (Chl) a and fucoxanthin intramolecular vibrations dominating over the first few picoseconds. Closer inspection of the spectral region of the Qy transition of Chl c revealed previously not identified, mutually non-interacting chlorophyll c states participating in femtosecond or picosecond energy transfer to the Chl a molecules. Consideration of separated coherent and incoherent dynamics allowed us to hypothesize the vibrations-assisted coherent energy transfer between Chl c and Chl a and the overall spatial arrangement of chlorophyll molecules.
authors.affiliation: Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 9-III, 10222 Vilnius, Lithuania.
authors.forename: Vytautas
authors.initials: V
authors.lastname: Butkus
authors.affiliation: Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 9-III, 10222 Vilnius, Lithuania.
authors.forename: Andrius
authors.initials: A
authors.lastname: Gelzinis
authors.affiliation: Center for Physical Sciences and Technology, Savanoriu Ave. 231, 02300 Vilnius, Lithuania.
authors.forename: Ramūnas
authors.initials: R
authors.lastname: Augulis
authors.affiliation: Institut de Biologie et Technologies de Saclay, Bât 532, Commissariat à l'Energie Atomique Saclay, 91191 Gif sur Yvette, France.
authors.forename: Andrew
authors.initials: A
authors.lastname: Gall
authors.affiliation: Institut für Molekulare Biowissenschaften, Universität Frankfurt, Max-von-Laue-Straße 9, Frankfurt, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Büchel
authors.affiliation: Institut de Biologie et Technologies de Saclay, Bât 532, Commissariat à l'Energie Atomique Saclay, 91191 Gif sur Yvette, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Robert
authors.affiliation: Department of Chemical Physics, Lund University, P.O. Box 124, 22100 Lund, Sweden.
authors.forename: Donatas
authors.initials: D
authors.lastname: Zigmantas
authors.affiliation: Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 9-III, 10222 Vilnius, Lithuania.
authors.forename: Leonas
authors.initials: L
authors.lastname: Valkunas
authors.affiliation: Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 9-III, 10222 Vilnius, Lithuania.
authors.forename: Darius
authors.initials: D
authors.lastname: Abramavicius
mesh_terms: D002734:Chlorophyll / Q000737:chemistry*; D004735:Energy Transfer; D045342:Light-Harvesting Protein Complexes / Q000737:chemistry*; D013057:Spectrum Analysis; D013816:Thermodynamics
chemical_list: D045342:Light-Harvesting Protein Complexes; C088752:fucoxanthin-, chlorophyll a-c-containing protein; D002734:Chlorophyll