- Group of open quantum systems (PI. prof. Darius Abramavičius)
- Group of Modeling of Dynamic Processes in Molecular Compounds (PI. prof. Leonas Valkūnas)
- Group of Quantum Chemistry (PI. prof. Juozas Šulskus)
About:
Excitation dynamics and decay kinetics in a photosynthetic molecular aggregates provide information on how plants perform solar energy conversion and hož they survive harsh environment conditions in Nature. The main pigments in Nature are chlorophylls and carotenoids. Their complexes in proteins are the major solar “powerplants” that power the life on Earth.
Excited states of molecular complexes are Frenkel excitons – collective excitations which cover several molecular entities. Mathematically accurate theoretical approaches have been developed for absorption, fluorescence and coherent nonlinear spectra of such molecular complexes. Such systems often demonstrate strong coupling between electronic and vibrational degrees of freedom. Time dependent variational approaches have been developed to characterize excitation dynamics in molecular systems that experience relaxation of the phonon bath in electronic excited states. This leads to a formation of polaron states. We have shown that molecular vibrations play an important role in maintaining high efficiency of the conversion processes.
Vibrational modes of various length carotenoid and polyene molecules was theoretically analysed using the density functional theory (DFT) approach. The different length carotenoids have linear correlation between the Raman ν1 band and electronic S0-S2 absorption. The possible distortions in carotenoids due to dimer effects may change the correlations what can be modelled by using DFT methods.
In extreme sun conditions plants switch on nonphotochemical quenching to survive the “overdose” conditions. Physical origin of so-called nonphotochemical quenching mechanism taking place in photosystem II of green plants has been studied. Our results show that the required level of photoprotection in vivo can be achieved by a very subtle change in the number of LHCIIs switched to the quenched state.
Computational approaches have been put together into a computer package QCFP.
Research interests:
- Characterization of the electric and magnetic responses of molecular materials of natural and artificial origin.
- Development of quantum relaxation theory and application to molecular systems.
- Development of theory of molecular excitations (excitons, polarons, vibrons) and application to molecular systems.
- Development of the computational approaches of nonlinear spectroscopy of molecular complexes.
- Theoretical studies of temperature dependences of the fluorescence kinetics of photosynthetic light-harvesting complexes from plants at different level of aggregation.
- Modelling of single molecular spectroscopy data of molecular systems.
Main publications (2014-2018)
- Static and Dynamic Disorder in Bacterial Light-Harvesting Complex LH2: A 2DES Simulation Study, Rancova, D. Abramavicius, J. Phys. Chem. B 118 , 7533, 2014
- Vibronic coherence in oxygenic photosynthesis F. D. Fuller, J. Pan, A. Gelzinis, V. Butkus, S. S. Senlik, D. E. Wilcox, C. F. Yocum, L. Valkunas, D. Abramavicius, J. P. Ogilvie, Nature Chem. 6 , 706-711 (2014).
- Probing environment fluctuations by two-dimensional electronic spectroscopy of molecular systems at temperatures below 5 K, Rancova, R. Jankowiak, D. Abramavicius, J. Chem. Phys, 142, 212428, 2015
- Vibronic energy relaxation approach highlighting deactivation pathways in carotenoids Balevičius, Jr. A. G. Pour, J. Savolainen, C. N. Lincoln, V. Lukeš , E. Riedle, L. Valkunas, D. Abramavicius, J. Hauer. Phys. Chem. Chem. Phys., 17 , 19491, 2015.
- Role of coherence and delocalization in photo-induced electron transfer at organic interfaces, V. Abramavicius, V. Pranculis, A. Melianas, O. Inganäs, V. Gulbinas, D. Abramavicius. Scientific Reports 6 , 32914, 2016.
- Chmeliov, J., Trinkunas, G., van Amerongen, H., Valkunas, L. Light harvesting in fluctuating antenna. Amer. Chem. Soc., 136: 8963-8972, 2014.
- Belgio, E., Kapitonova, E., Chmeliov, J., Duffy, C. D. P., Ungerer, P., Valkunas, L., Ruban, A. V. Economic photoprotection in photosystem II that retains a complete light-harvesting system with slow energy traps. Nature Comm., 5, 4433-1-8, 2014.
- Chmeliov, J., Gelzinis, A., Songaila, E., Augulis, R., Duffy, C. D. P., Ruban, A. V., Valkunas, L. The nature of self-regulation in photosynthetic light-harvesting antenna. Nature Plants 2: 16045, 2016.
- Chmeliov, J., Narkeliunas, J., Graham, M. W., Fleming, G. R., Valkunas, L. Exciton-exciton annihilation and relaxation pathways in semiconducting carbon nanotubes. Nanoscale 8: 1618-1626, 2016.
- Farooq, S., Chmeliov, J., Wientjes, E., Koehorst, R., Bader, A., Valkunas, L., Trinkunas, G., van Amerongen, H. Dynamic feedback of the photosystem II reaction centre on photoprotection in plants. Nature plants 4: 225-231, 2018.
Partners:
- Center of Physical Sciences and Technology (Lithuania)
- University of California, Berkeley
- University of California, Irvine (USA)
- University of Michigan, Ann Arbor (USA)
- Kansas State University (JAV)
- Queen Mary University, London (UK)
- Institute of Physics of Charles University (Czech Republic)
- Free University of Amsterdam (Netherlands)
- Free University of Brussels (Belgium)
- Lund University (Sweden)
- State key laboratory of supramolecular structure and materials, Jilin University (China)
Dalian Institute of Chemical Physics, Chineese Academy of Sciences (China) - University of Antwerp (Belgium)
University of Würzburg (Germany) - Munich Technical University (Germany)
- Institut de Biologie et de Technologie de Saclay, University Paris Sud, Gif sur Yvette (France)
- Bogolyubov Institute for Theoretical Physics, Ukrainian Academy of Sciences (Ukraine)
