1
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Schultz JD, Yuly JL, Arsenault EA, Parker K, Chowdhury SN, Dani R, Kundu S, Nuomin H, Zhang Z, Valdiviezo J, Zhang P, Orcutt K, Jang SJ, Fleming GR, Makri N, Ogilvie JP, Therien MJ, Wasielewski MR, Beratan DN. Coherence in Chemistry: Foundations and Frontiers. Chem Rev 2024; 124:11641-11766. [PMID: 39441172 DOI: 10.1021/acs.chemrev.3c00643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2024]
Abstract
Coherence refers to correlations in waves. Because matter has a wave-particle nature, it is unsurprising that coherence has deep connections with the most contemporary issues in chemistry research (e.g., energy harvesting, femtosecond spectroscopy, molecular qubits and more). But what does the word "coherence" really mean in the context of molecules and other quantum systems? We provide a review of key concepts, definitions, and methodologies, surrounding coherence phenomena in chemistry, and we describe how the terms "coherence" and "quantum coherence" refer to many different phenomena in chemistry. Moreover, we show how these notions are related to the concept of an interference pattern. Coherence phenomena are indeed complex, and ambiguous definitions may spawn confusion. By describing the many definitions and contexts for coherence in the molecular sciences, we aim to enhance understanding and communication in this broad and active area of chemistry.
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Affiliation(s)
- Jonathan D Schultz
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Jonathon L Yuly
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08540, United States
- Department of Physics, Duke University, Durham, North Carolina 27708, United States
| | - Eric A Arsenault
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Kelsey Parker
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Sutirtha N Chowdhury
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Reshmi Dani
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Sohang Kundu
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Hanggai Nuomin
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Zhendian Zhang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Jesús Valdiviezo
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts 02215, United States
- Sección Química, Departamento de Ciencias, Pontificia Universidad Católica del Perú, San Miguel, Lima 15088, Peru
| | - Peng Zhang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Kaydren Orcutt
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Bioproducts Research Unit, Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, 800 Buchanan Street, Albany, California 94710, United States
| | - Seogjoo J Jang
- Department of Chemistry and Biochemistry, Queens College, City University of New York, Queens, New York 11367, United States
- Chemistry and Physics PhD programs, Graduate Center, City University of New York, New York, New York 10016, United States
| | - Graham R Fleming
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
| | - Nancy Makri
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
- Department of Physics, University of Illinois, Urbana, Illinois 61801, United States
- Illinois Quantum Information Science and Technology Center, University of Illinois, Urbana, Illinois 61801, United States
| | - Jennifer P Ogilvie
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Michael J Therien
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Michael R Wasielewski
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - David N Beratan
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
- Department of Physics, Duke University, Durham, North Carolina 27708, United States
- Department of Biochemistry, Duke University, Durham, North Carolina 27710, United States
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2
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Fujimoto KJ, Tsuji R, Wang-Otomo ZY, Yanai T. Prominent Role of Charge Transfer in the Spectral Tuning of Photosynthetic Light-Harvesting I Complex. ACS PHYSICAL CHEMISTRY AU 2024; 4:499-509. [PMID: 39346607 PMCID: PMC11428290 DOI: 10.1021/acsphyschemau.4c00022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2024] [Revised: 07/24/2024] [Accepted: 07/24/2024] [Indexed: 10/01/2024]
Abstract
Purple bacteria possess two ring-shaped protein complexes, light-harvesting 1 (LH1) and 2 (LH2), both of which function as antennas for solar energy utilization for photosynthesis but exhibit distinct absorption properties. The two antennas have differing amounts of bacteriochlorophyll (BChl) a; however, their significance in spectral tuning remains elusive. Here, we report a high-precision evaluation of the physicochemical factors contributing to the variation in absorption maxima between LH1 and LH2, namely, BChl a structural distortion, protein electrostatic interaction, excitonic coupling, and charge transfer (CT) effects, as derived from detailed spectral calculations using an extended version of the exciton model, in the model purple bacterium Rhodospirillum rubrum. Spectral analysis confirmed that the electronic structure of the excited state in LH1 extended to the BChl a 16-mer. Further analysis revealed that the LH1-specific redshift (∼61% in energy) is predominantly accounted for by the CT effect resulting from the closer inter-BChl distance in LH1 than in LH2. Our analysis explains how LH1 and LH2, both with chemically identical BChl a chromophores, use distinct physicochemical effects to achieve a progressive redshift from LH2 to LH1, ensuring efficient energy transfer to the reaction center special pair.
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Affiliation(s)
- Kazuhiro J. Fujimoto
- Institute
of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan
- Department
of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan
| | - Rio Tsuji
- Department
of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan
| | | | - Takeshi Yanai
- Institute
of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan
- Department
of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan
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3
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Grechishnikova G, Wat JH, de Cordoba N, Miyake E, Phadkule A, Srivastava A, Savikhin S, Slipchenko L, Huang L, Reppert M. Controlling Vibronic Coupling in Chlorophyll Proteins: The Effects of Excitonic Delocalization and Vibrational Localization. J Phys Chem Lett 2024; 15:9456-9465. [PMID: 39250712 DOI: 10.1021/acs.jpclett.4c01826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/11/2024]
Abstract
Vibrational-electronic (vibronic) coupling plays a critical role in excitation energy transfer in molecular aggregates and pigment-protein complexes (PPCs). But the interplay between excitonic delocalization and vibronic interactions is complex, often leaving even qualitative questions as to what conceptual framework (e.g., Redfield versus Förster theory) should be used to interpret experimental results. To shed light on this issue, we report here on the interplay between excitonic delocalization and vibronic coupling in site-directed mutants of the water-soluble chlorophyll protein (WSCP), as reflected in 77 K fluorescence spectra. Experimentally, we find that in PPCs where excitonic delocalization is disrupted (either by mutagenesis or heterodimer formation), the relative intensity of the vibrational sideband (VSB) in fluorescence spectra is suppressed by up to 37% compared to that of the native protein. Numerical simulations reveal that this effect results from the localization of high-frequency vibrations in the coupled system; while excitonic delocalization suppresses the purely electronic transition due to H-aggregate-like dipole-dipole interference, high-frequency vibrations are unaffected, leading to a relative enhancement of the VSB. By comparing VSB intensities of PPCs both in the presence and absence of excitonic delocalization, we extract a set of "local" Huang-Rhys (HR) factors for Chl a in WSCP. More generally, our results suggest a significant role for geometric effects in controlling energy-transfer rates (which depend sensitively on absorption/fluorescence line shapes) in molecular aggregates and PPCs.
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Affiliation(s)
- Galina Grechishnikova
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jacob H Wat
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Nicolas de Cordoba
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Ethan Miyake
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Amala Phadkule
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Amit Srivastava
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Sergei Savikhin
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Lyudmila Slipchenko
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Libai Huang
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Mike Reppert
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
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4
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Drosou M, Bhattacharjee S, Pantazis DA. Combined Multireference-Multiscale Approach to the Description of Photosynthetic Reaction Centers. J Chem Theory Comput 2024; 20. [PMID: 39116215 PMCID: PMC11360140 DOI: 10.1021/acs.jctc.4c00578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 07/02/2024] [Accepted: 07/12/2024] [Indexed: 08/10/2024]
Abstract
A first-principles description of the primary photochemical processes that drive photosynthesis and sustain life on our planet remains one of the grand challenges of modern science. Recent research established that explicit incorporation of protein electrostatics in excited-state calculations of photosynthetic pigments, achieved for example with quantum-mechanics/molecular-mechanics (QM/MM) approaches, is essential for a meaningful description of the properties and function of pigment-protein complexes. Although time-dependent density functional theory has been used productively so far in QM/MM approaches for the study of such systems, this methodology has limitations. Here we pursue for the first time a QM/MM description of the reaction center in the principal enzyme of oxygenic photosynthesis, Photosystem II, using multireference wave function theory for the high-level QM region. We identify best practices and establish guidelines regarding the rational choice of active space and appropriate state-averaging for the efficient and reliable use of complete active space self-consistent field (CASSCF) and the N-electron valence state perturbation theory (NEVPT2) in the prediction of low-lying excited states of chlorophyll and pheophytin pigments. Given that the Gouterman orbitals are inadequate as a minimal active space, we define specific minimal and extended active spaces for the NEVPT2 description of electronic states that fall within the Q and B bands. Subsequently, we apply our multireference-QM/MM protocol to the description of all pigments in the reaction center of Photosystem II. The calculations reproduce the electrochromic shifts induced by the protein matrix and the ordering of site energies consistent with the identity of the primary donor (ChlD1) and the experimentally known asymmetric and directional electron transfer. The optimized protocol sets the stage for future multireference treatments of multiple pigments, and hence for multireference studies of charge separation, while it is transferable to the study of any photoactive embedded tetrapyrrole system.
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Affiliation(s)
- Maria Drosou
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Sinjini Bhattacharjee
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Dimitrios A. Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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5
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Saraceno P, Sardar S, Caferri R, Camargo FVA, Dall'Osto L, D'Andrea C, Bassi R, Cupellini L, Cerullo G, Mennucci B. Probing the Effect of Mutations on Light Harvesting in CP29 by Transient Absorption and First-Principles Simulations. J Phys Chem Lett 2024; 15:6398-6408. [PMID: 38861672 DOI: 10.1021/acs.jpclett.4c01040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2024]
Abstract
Natural light harvesting is exceptionally efficient thanks to the local energy funnel created within light-harvesting complexes (LHCs). To understand the design principles underlying energy transport in LHCs, ultrafast spectroscopy is often complemented by mutational studies that introduce perturbations into the excitonic structure of the natural complexes. However, such studies may fall short of identifying all excitation energy transfer (EET) pathways and their changes upon mutation. Here, we show that a synergistic combination of first-principles calculations and ultrafast spectroscopy can give unprecedented insight into the EET pathways occurring within LHCs. We measured the transient absorption spectra of the minor CP29 complex of plants and of two mutants, systematically mapping the kinetic components seen in experiments to the simulated exciton dynamics. With our combined strategy, we show that EET in CP29 is surprisingly robust to the changes in the exciton states induced by mutations, explaining the versatility of plant LHCs.
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Affiliation(s)
- Piermarco Saraceno
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, 56124 Pisa, Italy
| | - Samim Sardar
- Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, Via Rubattino 81, 20134 Milan, Italy
| | - Roberto Caferri
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Franco V A Camargo
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Piazza L. da Vinci 32, 20133 Milano, Italy
| | - Luca Dall'Osto
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Cosimo D'Andrea
- Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, Via Rubattino 81, 20134 Milan, Italy
- Dipartimento di Fisica, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milano, Italy
| | - Roberto Bassi
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Lorenzo Cupellini
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, 56124 Pisa, Italy
| | - Giulio Cerullo
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Piazza L. da Vinci 32, 20133 Milano, Italy
- Dipartimento di Fisica, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milano, Italy
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, 56124 Pisa, Italy
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6
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Betti E, Saraceno P, Cignoni E, Cupellini L, Mennucci B. Insights into Energy Transfer in Light-Harvesting Complex II Through Machine-Learning Assisted Simulations. J Phys Chem B 2024; 128:5188-5200. [PMID: 38761151 DOI: 10.1021/acs.jpcb.4c01494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2024]
Abstract
Light-harvesting complex II (LHCII) is the major antenna of higher plants. Energy transfer processes taking place inside its aggregate of chlorophylls have been experimentally investigated with time-resolved techniques, but a complete understanding of the most relevant energy transfer pathways and relative characteristic times remains elusive. Theoretical models to disentangle experimental data in LHCII have long been challenged by the large size and complex nature of the system. Here, we show that a fully first-principles approach combining molecular dynamics and machine learning can be successfully used to reproduce transient absorption spectra and characterize the EET pathways and the involved times.
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Affiliation(s)
- Elena Betti
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Piermarco Saraceno
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Edoardo Cignoni
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Lorenzo Cupellini
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
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7
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Saraceno P, Sláma V, Cupellini L. First-principles simulation of excitation energy transfer and transient absorption spectroscopy in the CP29 light-harvesting complex. J Chem Phys 2023; 159:184112. [PMID: 37962444 DOI: 10.1063/5.0170295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 10/24/2023] [Indexed: 11/15/2023] Open
Abstract
The dynamics of delocalized excitons in light-harvesting complexes (LHCs) can be investigated using different experimental techniques, and transient absorption (TA) spectroscopy is one of the most valuable methods for this purpose. A careful interpretation of TA spectra is essential for the clarification of excitation energy transfer (EET) processes occurring during light-harvesting. However, even in the simplest LHCs, a physical model is needed to interpret transient spectra as the number of EET processes occurring at the same time is very large to be disentangled from measurements alone. Physical EET models are commonly built by fittings of the microscopic exciton Hamiltonians and exciton-vibrational parameters, an approach that can lead to biases. Here, we present a first-principles strategy to simulate EET and transient absorption spectra in LHCs, combining molecular dynamics and accurate multiscale quantum chemical calculations to obtain an independent estimate of the excitonic structure of the complex. The microscopic parameters thus obtained are then used in EET simulations to obtain the population dynamics and the related spectroscopic signature. We apply this approach to the CP29 minor antenna complex of plants for which we follow the EET dynamics and transient spectra after excitation in the chlorophyll b region. Our calculations reproduce all the main features observed in the transient absorption spectra and provide independent insight on the excited-state dynamics of CP29. The approach presented here lays the groundwork for the accurate simulation of EET and unbiased interpretation of transient spectra in multichromophoric systems.
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Affiliation(s)
- Piermarco Saraceno
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy
| | - Vladislav Sláma
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy
| | - Lorenzo Cupellini
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy
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8
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Zerah Harush E, Dubi Y. Signature of Quantum Coherence in the Exciton Energy Pathways of the LH2 Photosynthetic Complex. ACS OMEGA 2023; 8:38871-38878. [PMID: 37901547 PMCID: PMC10601065 DOI: 10.1021/acsomega.3c02676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 06/15/2023] [Indexed: 10/31/2023]
Abstract
Unraveling the energy transfer pathways in photosynthetic complexes is an important step toward understanding their structure-function interplay. Here, we use an open quantum systems approach to investigate energy transfer within the LH2 photosynthetic apparatus and its dependence on environmental conditions. We find that energy transfer pathways strongly depend on the environment-induced dephasing time. A comparison between the computational results and experiments performed on similar systems demonstrates that quantum coherences are present in these systems under physiological conditions and have an important role in shaping the energy transfer pathways. Moreover, our calculations indicate that relatively simple spectroscopy experiments can be used to detect traces of quantum coherence. Finally, our results suggest that quantum coherence may play a role in photosynthesis, but not in enhancing the efficiency as was previously suggested.
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Affiliation(s)
- Elinor Zerah Harush
- Department of Chemistry and
Ilse Katz Center for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Yonatan Dubi
- Department of Chemistry and
Ilse Katz Center for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
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9
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Cupellini L, Qian P, Nguyen-Phan TC, Gardiner AT, Cogdell RJ. Quantum chemical elucidation of a sevenfold symmetric bacterial antenna complex. PHOTOSYNTHESIS RESEARCH 2023; 156:75-87. [PMID: 35672557 PMCID: PMC10070313 DOI: 10.1007/s11120-022-00925-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
The light-harvesting complex 2 (LH2) of purple bacteria is one of the most studied photosynthetic antenna complexes. Its symmetric structure and ring-like bacteriochlorophyll arrangement make it an ideal system for theoreticians and spectroscopists. LH2 complexes from most bacterial species are thought to have eightfold or ninefold symmetry, but recently a sevenfold symmetric LH2 structure from the bacterium Mch. purpuratum was solved by Cryo-Electron microscopy. This LH2 also possesses unique near-infrared absorption and circular dichroism (CD) spectral properties. Here we use an atomistic strategy to elucidate the spectral properties of Mch. purpuratum LH2 and understand the differences with the most commonly studied LH2 from Rbl. acidophilus. Our strategy exploits a combination of molecular dynamics simulations, multiscale polarizable quantum mechanics/molecular mechanics calculations, and lineshape simulations. Our calculations reveal that the spectral properties of LH2 complexes are tuned by site energies and exciton couplings, which in turn depend on the structural fluctuations of the bacteriochlorophylls. Our strategy proves effective in reproducing the absorption and CD spectra of the two LH2 complexes, and in uncovering the origin of their differences. This work proves that it is possible to obtain insight into the spectral tuning strategies of purple bacteria by quantitatively simulating the spectral properties of their antenna complexes.
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Affiliation(s)
- Lorenzo Cupellini
- Department of Chemistry and Industrial Chemistry, University of Pisa, 56124, Pisa, Italy.
| | - Pu Qian
- Materials and Structure Analysis, Thermofisher Scientific, Achtseweg Nordic 5, 5651 GTC, Eindhoven, The Netherlands
| | - Tu C Nguyen-Phan
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Alastair T Gardiner
- Laboratory of Anoxygenic Phototrophs, Centre Algatech, Novohradská 237 - Opatovický mlýn, 379 01, Třeboň, Czech Republic
| | - Richard J Cogdell
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
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10
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Exciton quantum dynamics in the molecular logic gates for quantum computing. Chem Phys 2023. [DOI: 10.1016/j.chemphys.2023.111860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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11
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Feighan O, Manby FR, Bourne-Worster S. An efficient protocol for excited states of large biochromophores. J Chem Phys 2023; 158:024107. [PMID: 36641400 DOI: 10.1063/5.0132417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Efficient energy transport in photosynthetic antenna is a long-standing source of inspiration for artificial light harvesting materials. However, characterizing the excited states of the constituent chromophores poses a considerable challenge to mainstream quantum chemical and semiempirical excited state methods due to their size and complexity and the accuracy required to describe small but functionally important changes in their properties. In this paper, we explore an alternative approach to calculating the excited states of large biochromophores, exemplified by a specific method for calculating the Qy transition of bacteriochlorophyll a, which we name Chl-xTB. Using a diagonally dominant approximation to the Casida equation and a bespoke parameterization scheme, Chl-xTB can match time-dependent density functional theory's accuracy and semiempirical speed for calculating the potential energy surfaces and absorption spectra of chlorophylls. We demonstrate that Chl-xTB (and other prospective realizations of our protocol) can be integrated into multiscale models, including concurrent excitonic and point-charge embedding frameworks, enabling the analysis of biochromophore networks in a native environment. We exploit this capability to probe the low-frequency spectral densities of excitonic energies and interchromophore interactions in the light harvesting antenna protein LH2 (light harvesting complex 2). The impact of low-frequency protein motion on interchromophore coupling and exciton transport has routinely been ignored due to the prohibitive costs of including it in simulations. Our results provide a more rigorous basis for continued use of this approximation by demonstrating that exciton transition energies are unaffected by low-frequency vibrational coupling to exciton interaction energies.
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Affiliation(s)
- Oliver Feighan
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
| | - Frederick R Manby
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
| | - Susannah Bourne-Worster
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
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12
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Nöthling JA, Mancal T, Kruger T. Accuracy of approximate methods for the calculation of absorption-type linear spectra with a complex system-bath coupling. J Chem Phys 2022; 157:095103. [DOI: 10.1063/5.0100977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The accuracy of approximate methods for calculating linear optical spectra depends on many variables. In this study, we fix most of these parameters to typical values found in photosynthetic light-harvesting complexes of plants and determine the accuracy of approximate spectra with respect to exact calculation as a function of the energy gap and interpigment coupling in a pigment dimer. We use a spectral density with the first eight intramolecular modes of chlorophyll a and include inhomogeneous disorder for the calculation of spectra. We compare the accuracy of absorption, linear dichroism, and circular dichroism spectra calculated using the Full Cumulant Expansion (FCE), coherent time-dependent Redfield (ctR), and time-independent Redfield and modified Redfield methods. As a reference we use spectra calculated with the Exact Stochastic Path Integral Evaluation method. We find the FCE method to be the most accurate for the calculation of all spectra. The ctR method performs well for the qualitative calculation of absorption and linear dichroism spectra when pigments are moderately coupled (∼15 cm-1), but ctR spectra may differ significantly from exact spectra when strong interpigment coupling (>100 cm-1) is present. The dependence of the quality of Redfield and modified Redfield spectra on molecular parameters is similar, and these methods almost always perform worse than ctR, especially when the interpigment coupling is strong or the excitonic energy gap is small (for a given coupling). The accuracy of approximate spectra is not affected by resonance with intramolecular modes for typical system-bath coupling and disorder values found in plant light-harvesting complexes.
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Affiliation(s)
| | - Tomas Mancal
- Faculty of Mathematics and Physics, Charles University Faculty of Mathematics and Physics, Czech Republic
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13
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Cignoni E, Slama V, Cupellini L, Mennucci B. The atomistic modeling of light-harvesting complexes from the physical models to the computational protocol. J Chem Phys 2022; 156:120901. [DOI: 10.1063/5.0086275] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The function of light-harvesting complexes is determined by a complex network of dynamic interactions among all the different components: the aggregate of pigments, the protein, and the surrounding environment. Complete and reliable predictions on these types of composite systems can be only achieved with an atomistic description. In the last few decades, there have been important advances in the atomistic modeling of light-harvesting complexes. These advances have involved both the completeness of the physical models and the accuracy and effectiveness of the computational protocols. In this Perspective, we present an overview of the main theoretical and computational breakthroughs attained so far in the field, with particular focus on the important role played by the protein and its dynamics. We then discuss the open problems in their accurate modeling that still need to be addressed. To illustrate an effective computational workflow for the modeling of light harvesting complexes, we take as an example the plant antenna complex CP29 and its H111N mutant.
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Affiliation(s)
- Edoardo Cignoni
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Vladislav Slama
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Lorenzo Cupellini
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
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14
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Cho KH, Rhee YM. Computational elucidations on the role of vibrations in energy transfer processes of photosynthetic complexes. Phys Chem Chem Phys 2021; 23:26623-26639. [PMID: 34842245 DOI: 10.1039/d1cp04615b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Coupling between pigment excitations and nuclear movements in photosynthetic complexes is known to modulate the excitation energy transfer (EET) efficiencies. Toward providing microscopic information, researchers often apply simulation techniques and investigate how vibrations are involved in EET processes. Here, reports on such roles of nuclear movements are discussed from a theory perspective. While vibrations naturally present random thermal fluctuations that can affect energy transferring characteristics, they can also be intertwined with exciton structures and create more specific non-adiabatic energy transfer pathways. For reliable simulations, a bath model that accurately mimics a given molecular system is required. Methods for obtaining such a model in combination with quantum chemical electronic structure calculations and molecular dynamics trajectory simulations are discussed. Various quantum dynamics simulation tools that can handle pigment-to-pigment energy transfers together with their vibrational characters are also touched on. Behaviors of molecular vibrations often deviate from ideality, especially when all-atom details are included, which practically forces us to treat them classically. We conclude this perspective by considering some recent reports that suggest that classical descriptions of bath effects with all-atom details may still produce valuable information for analyzing sophisticated contributions by vibrations to EET processes.
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Affiliation(s)
- Kwang Hyun Cho
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
| | - Young Min Rhee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
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15
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Abstract
Numerous linear and non-linear spectroscopic techniques have been developed to elucidate structural and functional information of complex systems ranging from natural systems, such as proteins and light-harvesting systems, to synthetic systems, such as solar cell materials and light-emitting diodes. The obtained experimental data can be challenging to interpret due to the complexity and potential overlapping spectral signatures. Therefore, computational spectroscopy plays a crucial role in the interpretation and understanding of spectral observables of complex systems. Computational modeling of various spectroscopic techniques has seen significant developments in the past decade, when it comes to the systems that can be addressed, the size and complexity of the sample types, the accuracy of the methods, and the spectroscopic techniques that can be addressed. In this Perspective, I will review the computational spectroscopy methods that have been developed and applied for infrared and visible spectroscopies in the condensed phase. I will discuss some of the questions that this has allowed answering. Finally, I will discuss current and future challenges and how these may be addressed.
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Affiliation(s)
- Thomas L C Jansen
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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16
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Fujimoto KJ, Minoda T, Yanai T. Spectral Tuning Mechanism of Photosynthetic Light-Harvesting Complex II Revealed by Ab Initio Dimer Exciton Model. J Phys Chem B 2021; 125:10459-10470. [PMID: 34521196 DOI: 10.1021/acs.jpcb.1c04457] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Excited states of two kinds of bacteriochlorophyll (BChl) aggregates, B850 and B800, in photosynthetic light-harvesting complex II (LH2) are theoretically investigated by developing and using an extended exciton model considering efficiently evaluated excitonic coupling. Our exciton model based on dimer fragmentation is shown to reproduce the experimental absorption spectrum of LH2 with good accuracy, entailing their different redshifts originating from aggregations of B850 and B800. The systematic analysis has been performed on the spectra by quantitatively decomposing their spectral shift energies into the contributions of various effects: structural distortion, electrostatic, excitonic coupling, and charge-transfer (CT) effects. Our results show that the spectral redshift of B800 is mainly attributed to its electrostatic interaction with the protein environment, while that of B850 arises from the marked effect of the excitonic coupling between BChl units. The interchromophore CT excitation also plays a key role in the spectral redshift of B850. This CT effect can be effectively described using our dimer model. This suited characterization reveals that the pronounced CT effect originates from the characteristics of B850 that has closely spaced BChls as dimers. We highlight the importance of the refinement of the crystal structure with the use of quantum chemical methods for prediction of the spectrum.
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Affiliation(s)
- Kazuhiro J Fujimoto
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furocho, Chikusa, Nagoya, 464-8601, Japan.,Department of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa, Nagoya, 464-8601, Japan
| | - Takumi Minoda
- Department of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa, Nagoya, 464-8601, Japan
| | - Takeshi Yanai
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furocho, Chikusa, Nagoya, 464-8601, Japan.,Department of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa, Nagoya, 464-8601, Japan
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17
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The Relationship between the Spatial Arrangement of Pigments and Exciton Transition Moments in Photosynthetic Light-Harvesting Complexes. Int J Mol Sci 2021; 22:ijms221810031. [PMID: 34576194 PMCID: PMC8470053 DOI: 10.3390/ijms221810031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 11/16/2022] Open
Abstract
Considering bacteriochlorophyll molecules embedded in the protein matrix of the light-harvesting complexes of purple bacteria (known as LH2 and LH1-RC) as examples of systems of interacting pigment molecules, we investigated the relationship between the spatial arrangement of the pigments and their exciton transition moments. Based on the recently reported crystal structures of LH2 and LH1-RC and the outcomes of previous theoretical studies, as well as adopting the Frenkel exciton Hamiltonian for two-level molecules, we performed visualizations of the LH2 and LH1 exciton transition moments. To make the electron transition moments in the exciton representation invariant with respect to the position of the system in space, a system of pigments must be translated to the center of mass before starting the calculations. As a result, the visualization of the transition moments for LH2 provided the following pattern: two strong transitions were outside of LH2 and the other two were perpendicular and at the center of LH2. The antenna of LH1-RC was characterized as having the same location of the strongest moments in the center of the complex, exactly as in the B850 ring, which actually coincides with the RC. Considering LH2 and LH1 as supermolecules, each of which has excitation energies and corresponding transition moments, we propose that the outer transitions of LH2 can be important for inter-complex energy exchange, while the inner transitions keep the energy in the complex; moreover, in the case of LH1, the inner transitions increased the rate of antenna-to-RC energy transfer.
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18
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19
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Maity S, Daskalakis V, Elstner M, Kleinekathöfer U. Multiscale QM/MM molecular dynamics simulations of the trimeric major light-harvesting complex II. Phys Chem Chem Phys 2021; 23:7407-7417. [PMID: 33876100 DOI: 10.1039/d1cp01011e] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Photosynthetic processes are driven by sunlight. Too little of it and the photosynthetic machinery cannot produce the reductive power to drive the anabolic pathways. Too much sunlight and the machinery can get damaged. In higher plants, the major Light-Harvesting Complex (LHCII) efficiently absorbs the light energy, but can also dissipate it when in excess (quenching). In order to study the dynamics related to the quenching process but also the exciton dynamics in general, one needs to accurately determine the so-called spectral density which describes the coupling between the relevant pigment modes and the environmental degrees of freedom. To this end, Born-Oppenheimer molecular dynamics simulations in a quantum mechanics/molecular mechanics (QM/MM) fashion utilizing the density functional based tight binding (DFTB) method have been performed for the ground state dynamics. Subsequently, the time-dependent extension of the long-range-corrected DFTB scheme has been employed for the excited state calculations of the individual chlorophyll-a molecules in the LHCII complex. The analysis of this data resulted in spectral densities showing an astonishing agreement with the experimental counterpart in this rather large system. This consistency with an experimental observable also supports the accuracy, robustness, and reliability of the present multi-scale scheme. To the best of our knowledge, this is the first theoretical attempt on this large complex system is ever made to accurately simulate the spectral density. In addition, the resulting spectral densities and site energies were used to determine the exciton transfer rate within a special pigment pair consisting of a chlorophyll-a and a carotenoid molecule which is assumed to play a role in the balance between the light harvesting and quenching modes.
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Affiliation(s)
- Sayan Maity
- Department of Physics and Earth Sciences, Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany.
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20
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Abstract
In this work, we outline a general method for calculating Auger spectra in molecules, which accounts for the underlying symmetry of the system. This theory starts from Fano’s formulation of the interaction between discrete and continuum states, and it generalizes this formalism to deal with the simultaneous presence of several intermediate quasi-bound states and several non-interacting decay channels. Our theoretical description is specifically tailored to resonant autoionization and Auger processes, and it explicitly includes the incoming wave boundary conditions for the continuum states and an accurate treatment of the Coulomb repulsion. This approach is implemented and applied to the calculation of the K−LL Auger and autoionization spectra of ozone, which is a C2v symmetric molecule, whose importance in our atmosphere to filter out radiation has been widely confirmed. We also show the effect that the molecular point group and, in particular, the localization of the core-hole in the oxygen atoms related by symmetry operations, has on the electronic structure of the Auger states and on the spectral lineshape by comparing our results with the experimental data.
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21
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Hashemi Z, Leppert L. Assessment of the Ab Initio Bethe-Salpeter Equation Approach for the Low-Lying Excitation Energies of Bacteriochlorophylls and Chlorophylls. J Phys Chem A 2021; 125:2163-2172. [PMID: 33656894 PMCID: PMC8028335 DOI: 10.1021/acs.jpca.1c01240] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bacteriochlorophyll and chlorophyll molecules are crucial building blocks of the photosynthetic apparatus in bacteria, algae, and plants. Embedded in transmembrane protein complexes, they are responsible for the primary processes of photosynthesis: excitation energy and charge transfer. Here, we use ab initio many-body perturbation theory within the GW approximation and Bethe-Salpeter equation (BSE) approach to calculate the electronic structure and optical excitations of bacteriochlorophylls a, b, c, d, and e and chlorophylls a and b. We systematically study the effects of the structure, basis set size, partial self-consistency in GW, and the underlying exchange-correlation approximation and compare our calculations with results from time-dependent density functional theory, multireference RASPT2, and experimental literature results. We find that optical excitations calculated with GW+BSE are in excellent agreement with experimental data, with an average deviation of less than 100 meV for the first three bright excitations of the entire family of (bacterio)chlorophylls. Contrary to state-of-the-art time-dependent density functional theory (TDDFT) with an optimally tuned range-separated hybrid functional, this accuracy is achieved in a parameter-free approach. Moreover, GW+BSE predicts the energy differences between the low-energy excitations correctly and eliminates spurious charge transfer states that TDDFT with (semi)local approximations is known to produce. Our study provides accurate reference results and highlights the potential of the GW+BSE approach for the simulation of larger pigment complexes.
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Affiliation(s)
- Zohreh Hashemi
- Institute of Physics, University of Bayreuth, Bayreuth 95440, Germany
| | - Linn Leppert
- Institute of Physics, University of Bayreuth, Bayreuth 95440, Germany.,MESA+ Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands
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22
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Osella S. Artificial Photosynthesis: Is Computation Ready for the Challenge Ahead? NANOMATERIALS 2021; 11:nano11020299. [PMID: 33498961 PMCID: PMC7911014 DOI: 10.3390/nano11020299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 01/19/2021] [Accepted: 01/20/2021] [Indexed: 12/13/2022]
Abstract
A tremendous effort is currently devoted to the generation of novel hybrid materials with enhanced electronic properties for the creation of artificial photosynthetic systems. This compelling and challenging problem is well-defined from an experimental point of view, as the design of such materials relies on combining organic materials or metals with biological systems like light harvesting and redox-active proteins. Such hybrid systems can be used, e.g., as bio-sensors, bio-fuel cells, biohybrid photoelectrochemical cells, and nanostructured photoelectronic devices. Despite these efforts, the main bottleneck is the formation of efficient interfaces between the biological and the organic/metal counterparts for efficient electron transfer (ET). It is within this aspect that computation can make the difference and improve the current understanding of the mechanisms underneath the interface formation and the charge transfer efficiency. Yet, the systems considered (i.e., light harvesting protein, self-assembly monolayer and surface assembly) are more and more complex, reaching (and often passing) the limit of current computation power. In this review, recent developments in computational methods for studying complex interfaces for artificial photosynthesis will be provided and selected cases discussed, to assess the inherent ability of computation to leave a mark in this field of research.
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Affiliation(s)
- Silvio Osella
- Chemical and Biological Systems Simulation Lab, Center of New Technologies, University of Warsaw, Banacha 2C, 02-097 Warsaw, Poland
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23
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Provazza J, Segatta F, Coker DF. Modeling Nonperturbative Field-Driven Vibronic Dynamics: Selective State Preparation and Nonlinear Spectroscopy. J Chem Theory Comput 2020; 17:29-39. [DOI: 10.1021/acs.jctc.0c01035] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Justin Provazza
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | - Francesco Segatta
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
- Dipartimento di Chimica Industriale “Toso Montanari”, University of Bologna, Viale del Risorgimento, 4, 40136 Bologna, Italy
| | - David F. Coker
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
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24
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Cupellini L, Lipparini F, Cao J. Absorption and Circular Dichroism Spectra of Molecular Aggregates With the Full Cumulant Expansion. J Phys Chem B 2020; 124:8610-8617. [PMID: 32901476 PMCID: PMC7901647 DOI: 10.1021/acs.jpcb.0c05180] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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The exciton Hamiltonian of multichromophoric aggregates can be probed by spectroscopic
techniques such as linear absorption and circular dichroism. To compare calculated
Hamiltonians to experiments, a lineshape theory is needed, which takes into account the
coupling of the excitons with inter- and intramolecular vibrations. This coupling is
normally introduced in a perturbative way through the cumulant expansion formalism and
further approximated by assuming a Markovian exciton dynamics, for example with the
modified Redfield theory. Here, we present the implementation of the full cumulant
expansion (FCE) formalism (142, 2015, 09410625747060) to
efficiently compute absorption and circular dichroism spectra of molecular aggregates
beyond the Markov approximation, without restrictions on the form of
exciton–phonon coupling. By employing the LH2 system of purple bacteria as a
challenging test case, we compare the FCE lineshapes with the Markovian lineshapes
obtained with the modified Redfield theory, showing that the latter presents a less
satisfying agreement with experiments. The FCE approach instead accurately describes the
lineshapes, especially in the vibronic sideband of the B800 peak. We envision that the
FCE approach will become a valuable tool for accurately comparing model exciton
Hamiltonians with optical spectroscopy experiments.
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Affiliation(s)
- Lorenzo Cupellini
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Filippo Lipparini
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Jianshu Cao
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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25
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Chen MS, Zuehlsdorff TJ, Morawietz T, Isborn CM, Markland TE. Exploiting Machine Learning to Efficiently Predict Multidimensional Optical Spectra in Complex Environments. J Phys Chem Lett 2020; 11:7559-7568. [PMID: 32808797 DOI: 10.1021/acs.jpclett.0c02168] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The excited-state dynamics of chromophores in complex environments determine a range of vital biological and energy capture processes. Time-resolved, multidimensional optical spectroscopies provide a key tool to investigate these processes. Although theory has the potential to decode these spectra in terms of the electronic and atomistic dynamics, the need for large numbers of excited-state electronic structure calculations severely limits first-principles predictions of multidimensional optical spectra for chromophores in the condensed phase. Here, we leverage the locality of chromophore excitations to develop machine learning models to predict the excited-state energy gap of chromophores in complex environments for efficiently constructing linear and multidimensional optical spectra. By analyzing the performance of these models, which span a hierarchy of physical approximations, across a range of chromophore-environment interaction strengths, we provide strategies for the construction of machine learning models that greatly accelerate the calculation of multidimensional optical spectra from first principles.
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Affiliation(s)
- Michael S Chen
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Tim J Zuehlsdorff
- Chemistry and Chemical Biology, University of California Merced, Merced, California 95343, United States
| | - Tobias Morawietz
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Christine M Isborn
- Chemistry and Chemical Biology, University of California Merced, Merced, California 95343, United States
| | - Thomas E Markland
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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26
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Conti I, Cerullo G, Nenov A, Garavelli M. Ultrafast Spectroscopy of Photoactive Molecular Systems from First Principles: Where We Stand Today and Where We Are Going. J Am Chem Soc 2020; 142:16117-16139. [PMID: 32841559 PMCID: PMC7901644 DOI: 10.1021/jacs.0c04952] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
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Computational spectroscopy is becoming a mandatory tool for the interpretation of the
complex, and often congested, spectral maps delivered by modern non-linear multi-pulse
techniques. The fields of Electronic Structure Methods,
Non-Adiabatic Molecular Dynamics, and Theoretical
Spectroscopy represent the three pillars of the virtual ultrafast
optical spectrometer, able to deliver transient spectra in
silico from first principles. A successful simulation strategy requires a
synergistic approach that balances between the three fields, each one having its very
own challenges and bottlenecks. The aim of this Perspective is to demonstrate that,
despite these challenges, an impressive agreement between theory and experiment is
achievable now regarding the modeling of ultrafast photoinduced processes in complex
molecular architectures. Beyond that, some key recent developments in the three fields
are presented that we believe will have major impacts on spectroscopic simulations in
the very near future. Potential directions of development, pending challenges, and
rising opportunities are illustrated.
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Affiliation(s)
- Irene Conti
- Dipartimento di Chimica Industriale, Università degli Studi di Bologna, Viale del Risorgimento 4, I-40136 Bologna, Italy
| | - Giulio Cerullo
- Dipartimento di Fisica, Politecnico di Milano, IFN-CNR, Piazza Leonardo da Vinci 32, I-20133 Milano, Italy
| | - Artur Nenov
- Dipartimento di Chimica Industriale, Università degli Studi di Bologna, Viale del Risorgimento 4, I-40136 Bologna, Italy
| | - Marco Garavelli
- Dipartimento di Chimica Industriale, Università degli Studi di Bologna, Viale del Risorgimento 4, I-40136 Bologna, Italy
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27
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Kozlov MI, Poddubnyy VV. Electron-Vibrational Spectra and Dynamics of the Lutein Molecule. J Phys Chem B 2020; 124:5780-5787. [PMID: 32573243 DOI: 10.1021/acs.jpcb.0c02511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The carotenoid molecules such as lutein play an important role in the absorption of light and the following transfer of energy during photosynthesis. However, the study of these processes by the experimental methods only is quite difficult because some of the transitions between the electronic states of carotenoids are optically forbidden and the effect of vibrational states change also must be taken into account. In the present work, electronic-vibrational states of the lutein molecule in the LHCII complex of higher plants and in the diethyl ether solution were described using the ab initio methods. For lutein of LHCII, the electronic energy transfer processes were modeled. The role of the "hot" S1 states of lutein was shown to be of great importance.
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Affiliation(s)
- Maxim I Kozlov
- Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia
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28
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Aquilante F, Autschbach J, Baiardi A, Battaglia S, Borin VA, Chibotaru LF, Conti I, De Vico L, Delcey M, Fdez Galván I, Ferré N, Freitag L, Garavelli M, Gong X, Knecht S, Larsson ED, Lindh R, Lundberg M, Malmqvist PÅ, Nenov A, Norell J, Odelius M, Olivucci M, Pedersen TB, Pedraza-González L, Phung QM, Pierloot K, Reiher M, Schapiro I, Segarra-Martí J, Segatta F, Seijo L, Sen S, Sergentu DC, Stein CJ, Ungur L, Vacher M, Valentini A, Veryazov V. Modern quantum chemistry with [Open]Molcas. J Chem Phys 2020; 152:214117. [PMID: 32505150 DOI: 10.1063/5.0004835] [Citation(s) in RCA: 250] [Impact Index Per Article: 62.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
MOLCAS/OpenMolcas is an ab initio electronic structure program providing a large set of computational methods from Hartree-Fock and density functional theory to various implementations of multiconfigurational theory. This article provides a comprehensive overview of the main features of the code, specifically reviewing the use of the code in previously reported chemical applications as well as more recent applications including the calculation of magnetic properties from optimized density matrix renormalization group wave functions.
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Affiliation(s)
- Francesco Aquilante
- Theory and Simulation of Materials (THEOS) and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jochen Autschbach
- Department of Chemistry, University at Buffalo, Buffalo, New York 14260-3000, USA
| | - Alberto Baiardi
- Laboratory of Physical Chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - Stefano Battaglia
- Department of Chemistry - BMC, Uppsala University, P.O. Box 576, SE-751 23 Uppsala, Sweden
| | - Veniamin A Borin
- Fritz Haber Center for Molecular Dynamics Research, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Liviu F Chibotaru
- Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
| | - Irene Conti
- Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna, Viale del Risorgimento 4, Bologna I-40136, Italy
| | - Luca De Vico
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, via Aldo Moro 2, 53100 Siena, Italy
| | - Mickaël Delcey
- Department of Chemistry - Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden
| | - Ignacio Fdez Galván
- Department of Chemistry - BMC, Uppsala University, P.O. Box 576, SE-751 23 Uppsala, Sweden
| | - Nicolas Ferré
- Aix-Marseille University, CNRS, Institut Chimie Radicalaire, Marseille, France
| | - Leon Freitag
- Laboratory of Physical Chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - Marco Garavelli
- Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna, Viale del Risorgimento 4, Bologna I-40136, Italy
| | - Xuejun Gong
- Department of Chemistry, University of Singapore, 3 Science Drive 3, 117543 Singapore
| | - Stefan Knecht
- Laboratory of Physical Chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - Ernst D Larsson
- Division of Theoretical Chemistry, Lund University, P.O. Box 124, Lund 22100, Sweden
| | - Roland Lindh
- Department of Chemistry - BMC, Uppsala University, P.O. Box 576, SE-751 23 Uppsala, Sweden
| | - Marcus Lundberg
- Department of Chemistry - Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden
| | - Per Åke Malmqvist
- Division of Theoretical Chemistry, Lund University, P.O. Box 124, Lund 22100, Sweden
| | - Artur Nenov
- Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna, Viale del Risorgimento 4, Bologna I-40136, Italy
| | - Jesper Norell
- Department of Physics, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Michael Odelius
- Department of Physics, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Massimo Olivucci
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, via Aldo Moro 2, 53100 Siena, Italy
| | - Thomas B Pedersen
- Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
| | - Laura Pedraza-González
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, via Aldo Moro 2, 53100 Siena, Italy
| | - Quan M Phung
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8602, Japan
| | - Kristine Pierloot
- Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
| | - Markus Reiher
- Laboratory of Physical Chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - Igor Schapiro
- Fritz Haber Center for Molecular Dynamics Research, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Javier Segarra-Martí
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, 80 Wood Lane, London W12 0BZ, United Kingdom
| | - Francesco Segatta
- Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna, Viale del Risorgimento 4, Bologna I-40136, Italy
| | - Luis Seijo
- Departamento de Química, Instituto Universitario de Ciencia de Materiales Nicolás Cabrera, and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Saumik Sen
- Fritz Haber Center for Molecular Dynamics Research, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | | | - Christopher J Stein
- Laboratory of Physical Chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - Liviu Ungur
- Department of Chemistry, University of Singapore, 3 Science Drive 3, 117543 Singapore
| | - Morgane Vacher
- Laboratoire CEISAM - UMR CNRS 6230, Université de Nantes, 44300 Nantes, France
| | - Alessio Valentini
- Theoretical Physical Chemistry, Research Unit MolSys, Université de Liège, Allée du 6 Août, 11, 4000 Liège, Belgium
| | - Valera Veryazov
- Division of Theoretical Chemistry, Lund University, P.O. Box 124, Lund 22100, Sweden
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29
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Liguori N, Croce R, Marrink SJ, Thallmair S. Molecular dynamics simulations in photosynthesis. PHOTOSYNTHESIS RESEARCH 2020; 144:273-295. [PMID: 32297102 PMCID: PMC7203591 DOI: 10.1007/s11120-020-00741-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 03/24/2020] [Indexed: 05/12/2023]
Abstract
Photosynthesis is regulated by a dynamic interplay between proteins, enzymes, pigments, lipids, and cofactors that takes place on a large spatio-temporal scale. Molecular dynamics (MD) simulations provide a powerful toolkit to investigate dynamical processes in (bio)molecular ensembles from the (sub)picosecond to the (sub)millisecond regime and from the Å to hundreds of nm length scale. Therefore, MD is well suited to address a variety of questions arising in the field of photosynthesis research. In this review, we provide an introduction to the basic concepts of MD simulations, at atomistic and coarse-grained level of resolution. Furthermore, we discuss applications of MD simulations to model photosynthetic systems of different sizes and complexity and their connection to experimental observables. Finally, we provide a brief glance on which methods provide opportunities to capture phenomena beyond the applicability of classical MD.
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Affiliation(s)
- Nicoletta Liguori
- Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Faculty of Sciences, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands.
| | - Roberta Croce
- Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Faculty of Sciences, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands
| | - Siewert J Marrink
- Groningen Biomolecular Sciences and Biotechnology Institute & Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Sebastian Thallmair
- Groningen Biomolecular Sciences and Biotechnology Institute & Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands.
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30
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Bold BM, Sokolov M, Maity S, Wanko M, Dohmen PM, Kranz JJ, Kleinekathöfer U, Höfener S, Elstner M. Benchmark and performance of long-range corrected time-dependent density functional tight binding (LC-TD-DFTB) on rhodopsins and light-harvesting complexes. Phys Chem Chem Phys 2020; 22:10500-10518. [PMID: 31950960 DOI: 10.1039/c9cp05753f] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The chromophores of rhodopsins (Rh) and light-harvesting (LH) complexes still represent a major challenge for a quantum chemical description due to their size and complex electronic structure. Since gradient corrected and hybrid density functional approaches have been shown to fail for these systems, only range-separated functionals seem to be a promising alternative to the more time consuming post-Hartree-Fock approaches. For extended sampling of optical properties, however, even more approximate approaches are required. Recently, a long-range corrected (LC) functional has been implemented into the efficient density functional tight binding (DFTB) method, allowing to sample the excited states properties of chromophores embedded into proteins using quantum mechanical/molecular mechanical (QM/MM) with the time-dependent (TD) DFTB approach. In the present study, we assess the accuracy of LC-TD-DFT and LC-TD-DFTB for rhodopsins (bacteriorhodopsin (bR) and pharaonis phoborhodopsin (ppR)) and LH complexes (light-harvesting complex II (LH2) and Fenna-Matthews-Olson (FMO) complex). This benchmark study shows the improved description of the color tuning parameters compared to standard DFT functionals. In general, LC-TD-DFTB can exhibit a similar performance as the corresponding LC functionals, allowing a reliable description of excited states properties at significantly reduced cost. The two chromophores investigated here pose complementary challenges: while huge sensitivity to external field perturbation (color tuning) and charge transfer excitations are characteristic for the retinal chromophore, the multi-chromophoric character of the LH complexes emphasizes a correct description of inter-chromophore couplings, giving less importance to color tuning. None of the investigated functionals masters both systems simultaneously with satisfactory accuracy. LC-TD-DFTB, at the current stage, although showing a systematic improvement compared to TD-DFTB cannot be recommended for studying color tuning in retinal proteins, similar to some of the LC-DFT functionals, because the response to external fields is still too weak. For sampling of LH-spectra, however, LC-TD-DFTB is a viable tool, allowing to efficiently sample absorption energies, as shown for three different LH complexes. As the calculations indicate, geometry optimization may overestimate the importance of local minima, which may be averaged over when using trajectories. Fast quantum chemical approaches therefore may allow for a direct sampling of spectra in the near future.
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Affiliation(s)
- Beatrix M Bold
- Institute of Physical Chemistry, Karlsruhe Institute of Technology (KIT), Kaiserstrasse 12, 76131 Karlsruhe, Germany.
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31
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Groenhof G, Modi V, Morozov D. Observe while it happens: catching photoactive proteins in the act with non-adiabatic molecular dynamics simulations. Curr Opin Struct Biol 2020; 61:106-112. [PMID: 31927414 DOI: 10.1016/j.sbi.2019.12.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 12/14/2019] [Indexed: 01/24/2023]
Abstract
Organisms use photo-receptors to react to light. The first step is usually the absorption of a photon by a prosthetic group embedded inside the photo-receptor, often a conjugated chromophore. The electronic changes in the chromophore induced by photo-absorption can trigger a cascade of structural or chemical transformations that culminate into a response to light. Understanding how these proteins have evolved to mediate their activation process has remained challenging because the required time and spacial resolutions are notoriously difficult to achieve experimentally. Therefore, mechanistic insights into photoreceptor activation have been predominantly obtained with computer simulations. Here we briefly outline the challenges associated with such computations and review the progress made in this field.
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Affiliation(s)
- Gerrit Groenhof
- Nanoscience Center and Department of Chemistry, P.O. Box 35, 40014 University of Jyväskylä, Finland.
| | - Vaibhav Modi
- Nanoscience Center and Department of Chemistry, P.O. Box 35, 40014 University of Jyväskylä, Finland
| | - Dmitry Morozov
- Nanoscience Center and Department of Chemistry, P.O. Box 35, 40014 University of Jyväskylä, Finland
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32
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Segarra-Martí J, Segatta F, Mackenzie TA, Nenov A, Rivalta I, Bearpark MJ, Garavelli M. Modeling multidimensional spectral lineshapes from first principles: application to water-solvated adenine. Faraday Discuss 2020; 221:219-244. [DOI: 10.1039/c9fd00072k] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We theoretically describe spectral lineshape from first principles, providing insight into solvent–solute interactions in terms of static and dynamic disorder and how these shape experimental signals in linear and non-linear optical spectroscopies.
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Affiliation(s)
- Javier Segarra-Martí
- Department of Chemistry
- Molecular Sciences Research Hub
- Imperial College London
- London
- UK
| | - Francesco Segatta
- Dipartimento di Chimica Industriale “Toso Montanari”
- Università degli studi di Bologna
- 40136 Bologna
- Italy
| | - Tristan A. Mackenzie
- Department of Chemistry
- Molecular Sciences Research Hub
- Imperial College London
- London
- UK
| | - Artur Nenov
- Dipartimento di Chimica Industriale “Toso Montanari”
- Università degli studi di Bologna
- 40136 Bologna
- Italy
| | - Ivan Rivalta
- Dipartimento di Chimica Industriale “Toso Montanari”
- Università degli studi di Bologna
- 40136 Bologna
- Italy
- Univ Lyon
| | - Michael J. Bearpark
- Department of Chemistry
- Molecular Sciences Research Hub
- Imperial College London
- London
- UK
| | - Marco Garavelli
- Dipartimento di Chimica Industriale “Toso Montanari”
- Università degli studi di Bologna
- 40136 Bologna
- Italy
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33
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Schelter I, Foerster JM, Gardiner AT, Roszak AW, Cogdell RJ, Ullmann GM, de Queiroz TB, Kümmel S. Assessing density functional theory in real-time and real-space as a tool for studying bacteriochlorophylls and the light-harvesting complex 2. J Chem Phys 2019; 151:134114. [DOI: 10.1063/1.5116779] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- Ingo Schelter
- Theoretical Physics IV, University of Bayreuth, Bayreuth, Germany
| | - Johannes M. Foerster
- Theoretical Physics IV and Computational Biochemistry, University of Bayreuth, Bayreuth, Germany
| | | | - Aleksander W. Roszak
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | - Richard J. Cogdell
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | | | | | - Stephan Kümmel
- Theoretical Physics IV, University of Bayreuth, Bayreuth, Germany
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34
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Cho KH, Chung S, Rhee YM. Efficiently Transplanting Potential Energy Interpolation Database between Two Systems: Bacteriochlorophyll Case with FMO and LH2 Complexes. J Chem Inf Model 2019; 59:4228-4238. [PMID: 31487163 DOI: 10.1021/acs.jcim.9b00472] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Generating a reliable potential energy surface (PES) is an important issue for studying the dynamics of any system with computational simulations. Interpolation mechanics/molecular mechanics (IM/MM) based on a PES interpolation scheme is a useful tool in that regard as it provides an accuracy of a quantum chemistry (QC) level while maintaining its computational cost comparable to conventional MM force fields. Despite this benefit, constructing the database for interpolation itself is still challenging and time-consuming. Here, we present a method with which we can construct the IM database of one system based on a preexisting data set for another related system. We adopt the case of constructing bacteriochlorophyll PESs for the light-harvesting 2 (LH2) complex by utilizing already available IM database for the BChls from the Fenna-Matthews-Olson (FMO) complex. In this method, the IM database from FMO is first transplanted to LH2 by considering BChl displacement vectors that take into account the geometry differences induced by the protein scaffolds. From this transplanted primitive database entries, a relatively small number of effective ones are selected by a survival process based on a genetic algorithm such that the IM energies evaluated at geometries in a conveniently collected prediction set can closely match with the reference QC energies. The selection process is expedited by using two different levels of basis sets for the QC calculations. To demonstrate the utility of the PES thus constructed, we carry out 1 ns of IM/MM dynamics simulations with the finally optimized BChl database for LH2. Indeed, the energy profiles of the snapshots are found to be closely matching with the reference QC calculation data, with only ∼0.07 eV of errors in the ground- and excited-state energies and ∼0.008 eV of errors in the transition energies. We also show that properly selecting data points is actually quite important for generating an IM PES toward performing molecular dynamics simulations.
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Affiliation(s)
- Kwang Hyun Cho
- Department of Chemistry , Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141 , Korea
| | - Seyoung Chung
- Department of Chemistry , Pohang University of Science and Technology (POSTECH) , Pohang 37673 , Korea
| | - Young Min Rhee
- Department of Chemistry , Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141 , Korea
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35
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Segatta F, Cupellini L, Garavelli M, Mennucci B. Quantum Chemical Modeling of the Photoinduced Activity of Multichromophoric Biosystems. Chem Rev 2019; 119:9361-9380. [PMID: 31276384 PMCID: PMC6716121 DOI: 10.1021/acs.chemrev.9b00135] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Indexed: 01/21/2023]
Abstract
Multichromophoric biosystems represent a broad family with very diverse members, ranging from light-harvesting pigment-protein complexes to nucleic acids. The former are designed to capture, harvest, efficiently transport, and transform energy from sunlight for photosynthesis, while the latter should dissipate the absorbed radiation as quickly as possible to prevent photodamages and corruption of the carried genetic information. Because of the unique electronic and structural characteristics, the modeling of their photoinduced activity is a real challenge. Numerous approaches have been devised building on the theoretical development achieved for single chromophores and on model Hamiltonians that capture the essential features of the system. Still, a question remains: is a general strategy for the accurate modeling of multichromophoric systems possible? By using a quantum chemical point of view, here we review the advancements developed so far highlighting differences and similarities with the single chromophore treatment. Finally, we outline the important limitations and challenges that still need to be tackled to reach a complete and accurate picture of their photoinduced properties and dynamics.
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Affiliation(s)
- Francesco Segatta
- Dipartimento
di Chimica Industriale “Toso Montanari” University of Bologna, Viale del Risorgimento 4, 40136 Bologna, Italy
| | - Lorenzo Cupellini
- Dipartimento
di Chimica e Chimica Industriale, University
of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Marco Garavelli
- Dipartimento
di Chimica Industriale “Toso Montanari” University of Bologna, Viale del Risorgimento 4, 40136 Bologna, Italy
| | - Benedetta Mennucci
- Dipartimento
di Chimica e Chimica Industriale, University
of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
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36
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Cupellini L, Bondanza M, Nottoli M, Mennucci B. Successes & challenges in the atomistic modeling of light-harvesting and its photoregulation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1861:148049. [PMID: 31386831 DOI: 10.1016/j.bbabio.2019.07.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/10/2019] [Accepted: 07/15/2019] [Indexed: 12/21/2022]
Abstract
Light-harvesting is a crucial step of photosynthesis. Its mechanisms and related energetics have been revealed by a combination of experimental investigations and theoretical modeling. The success of theoretical modeling is largely due to the application of atomistic descriptions combining quantum chemistry, classical models and molecular dynamics techniques. Besides the important achievements obtained so far, a complete and quantitative understanding of how the many different light-harvesting complexes exploit their structural specificity is still missing. Moreover, many questions remain unanswered regarding the mechanisms through which light-harvesting is regulated in response to variable light conditions. Here we show that, in both fields, a major role will be played once more by atomistic descriptions, possibly generalized to tackle the numerous time and space scales on which the regulation takes place: going from the ultrafast electronic excitation of the multichromophoric aggregate, through the subsequent conformational changes in the embedding protein, up to the interaction between proteins.
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Affiliation(s)
- Lorenzo Cupellini
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, Pisa 56124, Italy
| | - Mattia Bondanza
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, Pisa 56124, Italy
| | - Michele Nottoli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, Pisa 56124, Italy
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, Pisa 56124, Italy.
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37
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Anda A, Hansen T, De Vico L. Qy and Qx Absorption Bands for Bacteriochlorophyll a Molecules from LH2 and LH3. J Phys Chem A 2019; 123:5283-5292. [DOI: 10.1021/acs.jpca.9b02877] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- André Anda
- Chemical and Quantum Physics, School of Science, RMIT University, Melbourne, VIC 3001, Australia
- ARC Centre of Excellence in Exciton Science, School of Science, RMIT University, Melbourne, VIC 3001, Australia
| | - Thorsten Hansen
- Department of Chemistry, Copenhagen University, Universitetsparken 5, DK-2100, Copenhagen Ø, Denmark
| | - Luca De Vico
- Department of Biotechnologies, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, I-53100, Siena, Italy
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38
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Carli M, Turelli M, Faccioli P. Microscopic calculation of absorption spectra of macromolecules: An analytic approach. J Chem Phys 2019; 150:144103. [PMID: 30981270 DOI: 10.1063/1.5084120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We develop a cross-disciplinary approach to analytically compute optical response functions of open macromolecular systems by exploiting the mathematical formalism of quantum field theory (QFT). Indeed, the entries of the density matrix for the electronic excitations interacting with their open dissipative environment are mapped into vacuum-to-vacuum Green's functions in a fictitious relativistic closed quantum system. We show that by re-summing appropriate self-energy diagrams in this dual QFT, it is possible to obtain analytic expressions for the response functions in Mukamel's theory. This yields physical insight into the structure and dynamics of vibronic resonances, since their frequency and width is related to fundamental physical constants and microscopic model parameters. For illustration, we apply this scheme to compute the linear absorption spectrum of the Fenna-Matthews-Olson light harvesting complex, comparing analytic calculations, numerical Monte Carlo simulations, and experimental data.
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Affiliation(s)
- Matteo Carli
- Physics Department of Trento University, Via Sommarive 14, Povo, Trento 38123, Italy
| | - Michele Turelli
- Physics Department of Trento University, Via Sommarive 14, Povo, Trento 38123, Italy
| | - Pietro Faccioli
- Physics Department of Trento University, Via Sommarive 14, Povo, Trento 38123, Italy
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39
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40
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Jain A, Petit AS, Anna JM, Subotnik JE. Simple and Efficient Theoretical Approach To Compute 2D Optical Spectra. J Phys Chem B 2019; 123:1602-1617. [DOI: 10.1021/acs.jpcb.8b08674] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Amber Jain
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Andrew S. Petit
- Department of Chemistry and Biochemistry, California State University, Fullerton, California 92834, United States
| | - Jessica M. Anna
- Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Joseph E. Subotnik
- Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
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41
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Massey SC, Ting PC, Yeh SH, Dahlberg PD, Sohail SH, Allodi MA, Martin EC, Kais S, Hunter CN, Engel GS. Orientational Dynamics of Transition Dipoles and Exciton Relaxation in LH2 from Ultrafast Two-Dimensional Anisotropy. J Phys Chem Lett 2019; 10:270-277. [PMID: 30599133 DOI: 10.1021/acs.jpclett.8b03223] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Light-harvesting complexes in photosynthetic organisms display fast and efficient energy transfer dynamics, which depend critically on the electronic structure of the coupled chromophores within the complexes and their interactions with their environment. We present ultrafast anisotropy dynamics, resolved in both time and frequency, of the transmembrane light-harvesting complex LH2 from Rhodobacter sphaeroides in its native membrane environment using polarization-controlled two-dimensional electronic spectroscopy. Time-dependent anisotropy obtained from both experiment and modified Redfield simulation reveals an orientational preference for excited state absorption and an ultrafast equilibration within the B850 band in LH2. This ultrafast equilibration is favorable for subsequent energy transfer toward the reaction center. Our results also show a dynamic difference in excited state absorption anisotropy between the directly excited B850 population and the population that is initially excited at 800 nm, suggesting absorption from B850 states to higher-lying excited states following energy transfer from B850*. These results give insight into the ultrafast dynamics of bacterial light harvesting and the excited state energy landscape of LH2 in the native membrane environment.
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Affiliation(s)
- Sara C Massey
- Department of Chemistry, Institute for Biophysical Dynamics, and the James Franck Institute , The University of Chicago , Chicago , Illinois 60637 , United States
| | - Po-Chieh Ting
- Department of Chemistry, Institute for Biophysical Dynamics, and the James Franck Institute , The University of Chicago , Chicago , Illinois 60637 , United States
| | - Shu-Hao Yeh
- Department of Chemistry, Institute for Biophysical Dynamics, and the James Franck Institute , The University of Chicago , Chicago , Illinois 60637 , United States
- Qatar Environment and Energy Research Institute , Hamad Bin Khalifa University , Qatar Foundation, Doha , Qatar
| | - Peter D Dahlberg
- Graduate Program in the Biophysical Sciences, Institute for Biophysical Dynamics, and the James Franck Institute , The University of Chicago , Chicago , Illinois 60637 , United States
| | - Sara H Sohail
- Department of Chemistry, Institute for Biophysical Dynamics, and the James Franck Institute , The University of Chicago , Chicago , Illinois 60637 , United States
| | - Marco A Allodi
- Department of Chemistry, Institute for Biophysical Dynamics, and the James Franck Institute , The University of Chicago , Chicago , Illinois 60637 , United States
| | - Elizabeth C Martin
- Department of Molecular Biology and Biotechnology , University of Sheffield , Firth Court, Western Bank, Sheffield S10 2TN , United Kingdom
| | - Sabre Kais
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
| | - C Neil Hunter
- Department of Molecular Biology and Biotechnology , University of Sheffield , Firth Court, Western Bank, Sheffield S10 2TN , United Kingdom
| | - Gregory S Engel
- Department of Chemistry, Institute for Biophysical Dynamics, and the James Franck Institute , The University of Chicago , Chicago , Illinois 60637 , United States
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42
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Kim CW, Lee WG, Kim I, Rhee YM. Effect of Underdamped Vibration on Excitation Energy Transfer: Direct Comparison between Two Different Partitioning Schemes. J Phys Chem A 2019; 123:1186-1197. [DOI: 10.1021/acs.jpca.8b10977] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Chang Woo Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Weon-Gyu Lee
- Department of Chemistry, Sungkyunkwan University, Suwon 16419, Korea
| | - Inkoo Kim
- Samsung Advanced Institute of Technology, Samsung Electronics, 130 Samsung-ro, Yeongtong-gu, Suwon 16678, Korea
| | - Young Min Rhee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
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43
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Cupellini L, Caprasecca S, Guido CA, Müh F, Renger T, Mennucci B. Coupling to Charge Transfer States is the Key to Modulate the Optical Bands for Efficient Light Harvesting in Purple Bacteria. J Phys Chem Lett 2018; 9:6892-6899. [PMID: 30449098 DOI: 10.1021/acs.jpclett.8b03233] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The photosynthetic apparatus of purple bacteria uses exciton delocalization and static disorder to modulate the position and broadening of its absorption bands, leading to efficient light harvesting. Its main antenna complex, LH2, contains two rings of identical bacteriochlorophyll pigments, B800 and B850, absorbing at 800 and 850 nm, respectively. It has been an unsolved problem why static disorder of the strongly coupled B850 ring is several times larger than that of the B800 ring. Here we show that mixing between excitons and charge transfer states in the B850 ring is responsible for the effect. The linear absorption spectrum of the LH2 system is simulated by using a multiscale approach with an exciton Hamiltonian generalized to include the charge transfer states that involve adjacent pigment pairs, with static disorder modeled microscopically by molecular dynamics simulations. Our results show that sufficient inhomogeneous broadening of the B850 band, needed for efficient light harvesting, is only obtained by utilizing static disorder in the coupling between local excited and interpigment charge transfer states.
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Affiliation(s)
- Lorenzo Cupellini
- Dipartimento di Chimica e Chimica Industriale , University of Pisa , via G. Moruzzi 13 , 56124 Pisa , Italy
| | - Stefano Caprasecca
- Dipartimento di Chimica e Chimica Industriale , University of Pisa , via G. Moruzzi 13 , 56124 Pisa , Italy
| | - Ciro A Guido
- Dipartimento di Chimica e Chimica Industriale , University of Pisa , via G. Moruzzi 13 , 56124 Pisa , Italy
| | - Frank Müh
- Institute of Theoretical Physics, Department of Theoretical Biophysics , Johannes Kepler University Linz , Altenberger Strasse 69 , 4040 Linz , Austria
| | - Thomas Renger
- Institute of Theoretical Physics, Department of Theoretical Biophysics , Johannes Kepler University Linz , Altenberger Strasse 69 , 4040 Linz , Austria
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale , University of Pisa , via G. Moruzzi 13 , 56124 Pisa , Italy
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44
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Mallus MI, Shakya Y, Prajapati JD, Kleinekathöfer U. Environmental effects on the dynamics in the light-harvesting complexes LH2 and LH3 based on molecular simulations. Chem Phys 2018. [DOI: 10.1016/j.chemphys.2018.08.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Cupellini L, Corbella M, Mennucci B, Curutchet C. Electronic energy transfer in biomacromolecules. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2018. [DOI: 10.1002/wcms.1392] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Lorenzo Cupellini
- Dipartimento di Chimica e Chimica Industriale University of Pisa Pisa Italy
| | - Marina Corbella
- Departament de Farmàcia i Tecnologia Farmacèutica i Fisicoquímica and Institut de Química Teòrica i Computacional (IQTC‐UB), Facultat de Farmàcia i Ciències de l'Alimentació Universitat de Barcelona Barcelona Spain
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale University of Pisa Pisa Italy
| | - Carles Curutchet
- Departament de Farmàcia i Tecnologia Farmacèutica i Fisicoquímica and Institut de Química Teòrica i Computacional (IQTC‐UB), Facultat de Farmàcia i Ciències de l'Alimentació Universitat de Barcelona Barcelona Spain
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Segatta F, Gdor I, Réhault J, Taioli S, Friedman N, Sheves M, Rivalta I, Ruhman S, Cerullo G, Garavelli M. Ultrafast Carotenoid to Retinal Energy Transfer in Xanthorhodopsin Revealed by the Combination of Transient Absorption and Two-Dimensional Electronic Spectroscopy. Chemistry 2018; 24:12084-12092. [PMID: 30048017 DOI: 10.1002/chem.201803525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 07/26/2018] [Indexed: 11/10/2022]
Abstract
By comparing two-dimensional electronic spectroscopy (2DES) and Pump-Probe (PP) measurements on xanthorhodopsin (XR) and reduced-xanthorhodopsin (RXR) complexes, the ultrafast carotenoid-to-retinal energy transfer pathway is revealed, at very early times, by an excess of signal amplitude at the associated cross-peak and by the carotenoid bleaching reduction due to its ground state recovery. The combination of the measured 2DES and PP spectroscopic data with theoretical modelling allows a clear identification of the main experimental signals and a comprehensive interpretation of their origin and dynamics. The remarkable velocity of the energy transfer, despite the non-negligible energy separation between the two chromophores, and the analysis of the underlying transport mechanism, highlight the role played by the ground state carotenoid vibrations in assisting the process.
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Affiliation(s)
- Francesco Segatta
- European Center for Theoretical Studies in Nuclear Physics and Related Areas (ECT*-FBK), 38123, Trento, Italy.,Department of Industrial Chemistry, University of Bologna, Viale Risorgimento 4, 40136, Bologna, Italy
| | - Itay Gdor
- Department of Physical Chemistry, The Hebrew University, Jerusalem, 9190401, Israel
| | - Julien Réhault
- Department für Chemie und Biochemie, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Simone Taioli
- European Center for Theoretical Studies in Nuclear Physics and Related Areas (ECT*-FBK), 38123, Trento, Italy
| | - Noga Friedman
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Mordechai Sheves
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Ivan Rivalta
- Laboratoire de Chimie UMR 5182, Université Lyon, ENS de Lyon, CNRS, Unversité Lyon 1, Allée d'Italie 46, FR-69342, Lyon, France
| | - Sanford Ruhman
- Department of Physical Chemistry, The Hebrew University, Jerusalem, 9190401, Israel
| | - Giulio Cerullo
- Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy
| | - Marco Garavelli
- Department of Industrial Chemistry, University of Bologna, Viale Risorgimento 4, 40136, Bologna, Italy
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Ke Y, Zhao Y. Calculations of coherent two-dimensional electronic spectra using forward and backward stochastic wavefunctions. J Chem Phys 2018; 149:014104. [DOI: 10.1063/1.5037684] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Affiliation(s)
- Yaling Ke
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Yi Zhao
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
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Caprasecca S, Cupellini L, Jurinovich S, Loco D, Lipparini F, Mennucci B. A polarizable QM/MM description of environment effects on NMR shieldings: from solvated molecules to pigment–protein complexes. Theor Chem Acc 2018. [DOI: 10.1007/s00214-018-2264-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Kozlov MI, Poddubnyy VV, Glebov IO. Calculation of the excited states properties of LH1 complex of Thermochromatium tepidum. J Comput Chem 2018; 39:1599-1606. [PMID: 29701316 DOI: 10.1002/jcc.25232] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 03/28/2018] [Accepted: 04/03/2018] [Indexed: 11/09/2022]
Abstract
Calculation of the excited states properties of pigment complexes is one of the key problems in the photosynthesis research. The excited states of LH1 complex of Thermochromatium tepidum were studied by means of the high-precision quantum chemistry methods. The influence of different parameters of the calculation procedure was examined. The optimal scheme of calculation was chosen by comparison of calculated results with the experimental data on absorption, electronic and magnetic circular dichroism spectra. The high importance of the account of the second excited states of bacteriochlorophylls and of site heterogeneity was shown. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Maxim I Kozlov
- Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Vladimir V Poddubnyy
- Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Ilya O Glebov
- Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia, 119991
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50
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Montemayor D, Rivera E, Jang SJ. Computational Modeling of Exciton-Bath Hamiltonians for Light Harvesting 2 and Light Harvesting 3 Complexes of Purple Photosynthetic Bacteria at Room Temperature. J Phys Chem B 2018. [PMID: 29533664 DOI: 10.1021/acs.jpcb.8b00358] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Light harvesting 2 (LH2) complex is the primary component of the photosynthetic unit of purple bacteria that is responsible for harvesting and relaying excitons. The electronic absorption line shape of LH2 contains two major bands at 800 and 850 nm wavelength regions. Under low light conditions, some species of purple bacteria replace LH2 with light harvesting 3 (LH3), a variant form with almost the same structure as the former but with distinctively different spectral features. The major difference between the absorption line shapes of LH2 and LH3 is the shift of the 850 nm band of the former to a new 820 nm region. The microscopic origin of this difference has been the subject of some theoretical/computational investigations. However, the genuine molecular level source of such a difference is not clearly understood yet. This work reports a comprehensive computational study of LH2 and LH3 complexes so as to clarify different molecular level features of LH2 and LH3 complexes and to construct simple exciton-bath models with a common form. All-atomistic molecular dynamics simulations of both LH2 and LH3 complexes provide detailed molecular level structural differences of bacteriochlorophylls (BChls) in the two complexes, in particular, in their patterns of hydrogen bonding (HB) and torsional angles of the acetyl group. Time-dependent density functional theory calculation of the excitation energies of BChls for structures sampled from the MD simulations suggests that the observed differences in the HB and torsional angles cannot fully account for the experimentally observed spectral shift of LH3. Potential sources that can explain the actual spectral shift of LH3 are discussed, and their magnitudes are assessed through fitting of experimental line shapes. These results demonstrate the feasibility of developing simple exciton-bath models for both LH2 and LH3, which can be employed for large-scale exciton quantum dynamics in their aggregates.
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Affiliation(s)
- Daniel Montemayor
- Department of Chemistry and Biochemistry, Queens College , City University of New York , 65-30 Kissena Boulevard , Queens , New York 11367 , United States.,PhD Programs in Chemistry and Physics, and Initiative for the Theoretical Sciences, Graduate Center , City University of New York , 365 Fifth Avenue , New York , New York 10016 , United States
| | - Eva Rivera
- Department of Chemistry and Biochemistry, Queens College , City University of New York , 65-30 Kissena Boulevard , Queens , New York 11367 , United States.,PhD Programs in Chemistry and Physics, and Initiative for the Theoretical Sciences, Graduate Center , City University of New York , 365 Fifth Avenue , New York , New York 10016 , United States
| | - Seogjoo J Jang
- Department of Chemistry and Biochemistry, Queens College , City University of New York , 65-30 Kissena Boulevard , Queens , New York 11367 , United States.,PhD Programs in Chemistry and Physics, and Initiative for the Theoretical Sciences, Graduate Center , City University of New York , 365 Fifth Avenue , New York , New York 10016 , United States
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