1
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Jaiswal VK, Aranda Ruiz D, Petropoulos V, Kabaciński P, Montorsi F, Uboldi L, Ugolini S, Mukamel S, Cerullo G, Garavelli M, Santoro F, Nenov A. Sub-100-fs energy transfer in coenzyme NADH is a coherent process assisted by a charge-transfer state. Nat Commun 2024; 15:4900. [PMID: 38851775 PMCID: PMC11162464 DOI: 10.1038/s41467-024-48871-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 05/15/2024] [Indexed: 06/10/2024] Open
Abstract
Excitation energy transfer (EET) is a key photoinduced process in biological chromophoric assemblies. Here we investigate the factors which can drive EET into efficient ultrafast sub-ps regimes. We demonstrate how a coherent transport of electronic population could facilitate this in water solvated NADH coenzyme and uncover the role of an intermediate dark charge-transfer state. High temporal resolution ultrafast optical spectroscopy gives a 54±11 fs time constant for the EET process. Nonadiabatic quantum dynamical simulations computed through the time-evolution of multidimensional wavepackets suggest that the population transfer is mediated by photoexcited molecular vibrations due to strong coupling between the electronic states. The polar aqueous solvent environment leads to the active participation of a dark charge transfer state, accelerating the vibronically coherent EET process in favorably stacked conformers and solvent cavities. Our work demonstrates how the interplay of structural and environmental factors leads to diverse pathways for the EET process in flexible heterodimers and provides general insights relevant for coherent EET processes in stacked multichromophoric aggregates like DNA strands.
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Affiliation(s)
- Vishal Kumar Jaiswal
- Dipartimento di Chimica industriale "Toso Montanari", Università di Bologna, Viale del Risorgimento 4, 40136, Bologna, Italy
| | - Daniel Aranda Ruiz
- ICMol, Universidad de Valencia, Catedrático José Beltrán Martínez, 2, 46980, Paterna, Spain
| | - Vasilis Petropoulos
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy
| | - Piotr Kabaciński
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy
| | - Francesco Montorsi
- Dipartimento di Chimica industriale "Toso Montanari", Università di Bologna, Viale del Risorgimento 4, 40136, Bologna, Italy
| | - Lorenzo Uboldi
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy
| | - Simone Ugolini
- Dipartimento di Chimica industriale "Toso Montanari", Università di Bologna, Viale del Risorgimento 4, 40136, Bologna, Italy
| | - Shaul Mukamel
- Department of Chemistry and Department of Physics and Astronomy, University of California, Irvine, CA, 92697, USA
| | - Giulio Cerullo
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy.
| | - Marco Garavelli
- Dipartimento di Chimica industriale "Toso Montanari", Università di Bologna, Viale del Risorgimento 4, 40136, Bologna, Italy.
| | - Fabrizio Santoro
- Istituto di Chimica dei Composti Organometallici (ICCOM-CNR), Area della Ricerca del CNR, Via Moruzzi 1, I-56124, Pisa, Italy
| | - Artur Nenov
- Dipartimento di Chimica industriale "Toso Montanari", Università di Bologna, Viale del Risorgimento 4, 40136, Bologna, Italy.
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2
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Koga M, Kang DH, Heim ZN, Meyer P, Erickson BA, Haldar N, Baradaran N, Havenith M, Neumark DM. Extreme ultraviolet time-resolved photoelectron spectroscopy of adenine, adenosine and adenosine monophosphate in a liquid flat jet. Phys Chem Chem Phys 2024; 26:13106-13117. [PMID: 38629206 DOI: 10.1039/d4cp00856a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
Time-resolved photoelectron spectroscopy using an extreme-ultraviolet (XUV) probe pulse was used to investigate the UV photoinduced dynamics of adenine (Ade), adenosine (Ado), and adenosine-5-monophosphate (AMP) in a liquid water jet. In contrast to previous studies using UV probe pulses, the XUV pulse at 21.7 eV can photoionize all excited states of a molecule, allowing for full relaxation pathways to be addressed after excitation at 4.66 eV. This work was carried out using a gas-dynamic flat liquid jet, resulting in considerably enhanced signal compared to a cylindrical jet. All three species decay on multiple time scales that are assigned based on their decay associated spectra; the fastest decay of ∼100 fs is assigned to ππ* decay to the ground state, while a smaller component with a lifetime of ∼500 fs is attributed to the nπ* state. An additional slower channel in Ade is assigned to the 7H Ade conformer, as seen previously. This work demonstrates the capability of XUV-TRPES to disentangle non-adiabatic dynamics in an aqueous solution in a state-specific manner and represents the first identification of the nπ* state in the relaxation dynamics of adenine and its derivatives.
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Affiliation(s)
- Masafumi Koga
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
| | - Do Hyung Kang
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
| | - Zachary N Heim
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
| | - Philipp Meyer
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44801, Germany
| | - Blake A Erickson
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
| | - Neal Haldar
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
| | - Negar Baradaran
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
| | - Martina Havenith
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44801, Germany
| | - Daniel M Neumark
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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3
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Jaiswal VK, Taddei M, Nascimento DR, Garavelli M, Conti I, Nenov A. Reconciling TD-DFT and CASPT2 electronic structure methods for describing the photophysics of DNA. Photochem Photobiol 2024; 100:443-452. [PMID: 38356286 DOI: 10.1111/php.13922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 01/17/2024] [Accepted: 01/26/2024] [Indexed: 02/16/2024]
Abstract
Time-dependent density functional theory (TD-DFT) and multiconfigurational second-order perturbation theory (CASPT2) are two of the most widely used methods to investigate photoinduced dynamics in DNA-based systems. These methods sometimes give diverse dynamics in physiological environments usually modeled by quantum mechanics/molecular mechanics (QM/MM) protocol. In this work, we demonstrate for the uridine test case that the underlying topology of the potential energy surfaces of electronic states involved in photoinduced relaxation is similar in both electronic structure methods. This is verified by analyzing surface-hopping dynamics performed at the QM/MM level on aqueous solvated uridine at TD-DFT and CASPT2 levels. By constraining the dynamics to remain onπ π * state we observe similar fluctuations in energy and relaxation lifetimes in surface-hopping dynamics in both TD-DFT and experimentally validated CASPT2 methods. This finding calls for a systematic comparison of the ES potential energy surfaces of DNA and RNA nucleosides at the single- and multi-reference levels of theory. The anomalous long excited state lifetime at the TD-DFT level is explained byn π * trapping due to the tendency of TD-DFT in QM/MM schemes with electrostatic embedding to underestimate the energy of theπ π * state leading to a wrongπ π * / n π * energetic order. A study of the FC energetics suggests that improving the description of the surrounding environment through polarizable embedding or by the expansion of QM layer with hydrogen-bonded waters helps restore the correct state order at TD-DFT level. Thus by combining TDDFT with an accurate modeling of the environment, TD-DFT is positioned as the standout protocol to model photoinduced dynamics in DNA-based aggregates and multimers.
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Affiliation(s)
- Vishal Kumar Jaiswal
- Dipartimento di Chimica Industriale, Università degli Studi di Bologna, Bologna, Italy
| | - Mario Taddei
- Dipartimento di Chimica Industriale, Università degli Studi di Bologna, Bologna, Italy
| | | | - Marco Garavelli
- Dipartimento di Chimica Industriale, Università degli Studi di Bologna, Bologna, Italy
| | - Irene Conti
- Dipartimento di Chimica Industriale, Università degli Studi di Bologna, Bologna, Italy
| | - Artur Nenov
- Dipartimento di Chimica Industriale, Università degli Studi di Bologna, Bologna, Italy
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4
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Cuéllar-Zuquin J, Pepino AJ, Fdez. Galván I, Rivalta I, Aquilante F, Garavelli M, Lindh R, Segarra-Martí J. Characterizing Conical Intersections in DNA/RNA Nucleobases with Multiconfigurational Wave Functions of Varying Active Space Size. J Chem Theory Comput 2023; 19:8258-8272. [PMID: 37882796 PMCID: PMC10851440 DOI: 10.1021/acs.jctc.3c00577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 10/13/2023] [Accepted: 10/13/2023] [Indexed: 10/27/2023]
Abstract
We characterize the photochemically relevant conical intersections between the lowest-lying accessible electronic excited states of the different DNA/RNA nucleobases using Cholesky decomposition-based complete active space self-consistent field (CASSCF) algorithms. We benchmark two different basis set contractions and several active spaces for each nucleobase and conical intersection type, measuring for the first time how active space size affects conical intersection topographies in these systems and the potential implications these may have toward their description of photoinduced phenomena. Our results show that conical intersection topographies are highly sensitive to the electron correlation included in the model: by changing the amount (and type) of correlated orbitals, conical intersection topographies vastly change, and the changes observed do not follow any converging pattern toward the topographies obtained with the largest and most correlated active spaces. Comparison across systems shows analogous topographies for almost all intersections mediating population transfer to the dark 1nO/Nπ* states, while no similarities are observed for the "ethylene-like" conical intersection ascribed to mediate the ultrafast decay component to the ground state in all DNA/RNA nucleobases. Basis set size seems to have a minor effect, appearing to be relevant only for purine-based derivatives. We rule out structural changes as a key factor in classifying the different conical intersections, which display almost identical geometries across active space and basis set change, and we highlight instead the importance of correctly describing the electronic states involved at these crossing points. Our work shows that careful active space selection is essential to accurately describe conical intersection topographies and therefore to adequately account for their active role in molecular photochemistry.
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Affiliation(s)
- Juliana Cuéllar-Zuquin
- Instituto
de Ciencia Molecular, Universitat de Valencia, P.O. Box 22085, ES-46071 Valencia, Spain
| | - Ana Julieta Pepino
- Dipartimento
di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale del Risorgimento 4, I-40136 Bologna, Italy
| | - Ignacio Fdez. Galván
- Department
of Chemistry − BMC, Uppsala University, P.O. Box 576, SE-75123 Uppsala, Sweden
| | - Ivan Rivalta
- Dipartimento
di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale del Risorgimento 4, I-40136 Bologna, Italy
- ENSL,
CNRS, Laboratoire de Chimie UMR 5182, 46 Allée d’Italie, 69364 Lyon, France
| | - 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, CH-1015 Lausanne, Switzerland
| | - Marco Garavelli
- Dipartimento
di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale del Risorgimento 4, I-40136 Bologna, Italy
| | - Roland Lindh
- Department
of Chemistry − BMC, Uppsala University, P.O. Box 576, SE-75123 Uppsala, Sweden
| | - Javier Segarra-Martí
- Instituto
de Ciencia Molecular, Universitat de Valencia, P.O. Box 22085, ES-46071 Valencia, Spain
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5
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Ullah N, Chen S, Zhang R. Excited‐state nonadiabatic dynamics simulations on the heptazine and adenine in a water environment: A mini review. J CHIN CHEM SOC-TAIP 2023. [DOI: 10.1002/jccs.202200445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Naeem Ullah
- Department of Physics City University of Hong Kong Kowloon Hong Kong SAR China
- Department of Physics Government Degree College Dara Adam Khel, Higher Education Department Khyber Pakhtunkhwah Pakistan
| | - Shunwei Chen
- Department of Physics City University of Hong Kong Kowloon Hong Kong SAR China
- School of Materials Science and Engineering Qilu University of Technology (Shandong Academy of Sciences) Jinan China
| | - Ruiqin Zhang
- Department of Physics City University of Hong Kong Kowloon Hong Kong SAR China
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6
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Shahrokh L, Omidyan R, Azimi G. Excited State Deactivation Mechanisms of Protonated Adenine: a Theoretical study. Phys Chem Chem Phys 2022; 24:14898-14908. [DOI: 10.1039/d2cp00106c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Quantum chemical computational method as well as the adiabatic dynamics simulation have been employed to investigate the non-radiative relaxation mechanism of protonated 9H- and 7H-adenine (AH+). We have located three...
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7
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Ullah N, Chen S, Zhang R. Adenine ultrafast photorelaxation via electron-driven proton transfer. Phys Chem Chem Phys 2021; 23:23090-23095. [PMID: 34617085 DOI: 10.1039/d1cp03162g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photorelaxation of adenine in water was reported to be ultrafast (within 180 fs) primarily due to radiationless relaxation. However, in the last two decades, several experimental and theoretical investigations on photoexcitation of adenine have revealed diverse types of decay mechanisms. Using time-dependent density functional excited-state nonadiabatic dynamics simulations we show that it is the water to adenine electron-driven proton transfer (EDPT) barrierless reaction responsible for the ultrafast component of the adenine relaxation, which, however, occurred only in the case of the 7H isomer of adenine with five water molecules. This result reveals a known reaction pathway, however not found in previous simulations, with inference for the ultrafast relaxation mechanisms of adenine reported in experiments. The 9H isomer of adenine with six water molecules relaxing in a water cluster followed the previously known structural distortion (C2) decay pathway. The observations of the adenine EDPT reaction with water provide the origin of the experimental ultrafast adenine decay component and present a possible method to tackle future computational challenges in molecular-level biological processes.
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Affiliation(s)
- Naeem Ullah
- Department of Physics, City University of Hong Kong, Hong Kong SAR, China.
| | - Shunwei Chen
- School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Ruiqin Zhang
- Department of Physics, City University of Hong Kong, Hong Kong SAR, China. .,Beijing Computational Science Research Center, Beijing 100193, China
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8
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Castellani ME, Avagliano D, González L, Verlet JRR. Site-Specific Photo-oxidation of the Isolated Adenosine-5'-triphosphate Dianion Determined by Photoelectron Imaging. J Phys Chem Lett 2020; 11:8195-8201. [PMID: 32886886 DOI: 10.1021/acs.jpclett.0c02089] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Photoelectron imaging of the isolated adenosine-5'-triphosphate dianion excited to the 1ππ* states reveals that electron emission is predominantly parallel to the polarization axis of the light and arises from subpicosecond electron tunneling through the repulsive Coulomb barrier (RCB). The computed RCB shows that the most probable electron emission site is on the amino group of adenine. This is consistent with the photoelectron imaging: excitation to the 1ππ* states leads to an aligned ensemble distributed predominantly parallel to the long axis of adenine; the subsequent electron tunneling site is along this axis; and the negatively charged phosphate groups guide the outgoing electron mostly along this axis at long range. Imaging of electron tunneling from polyanions combined with computational chemistry may offer a general route for probing the intrinsic photo-oxidation site and dynamics as well as the overall structure of complex isolated species.
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Affiliation(s)
| | - Davide Avagliano
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria
| | - Leticia González
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria
| | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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9
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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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10
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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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11
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Fang YG, Peng Q, Fang Q, Fang W, Cui G. MS-CASPT2 Studies on the Photophysics of Selenium-Substituted Guanine Nucleobase. ACS OMEGA 2019; 4:9769-9777. [PMID: 31460068 PMCID: PMC6649137 DOI: 10.1021/acsomega.9b01276] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 05/23/2019] [Indexed: 05/30/2023]
Abstract
The MS-CASPT2 method has been employed to optimize minimum-energy structures of 6-selenoguanine (6SeGua) and related two- and three-state intersection structures in and between the lowest five electronic states, i.e., S2(1ππ*), S1(1 nπ*), T2(3 nπ*), T1(3ππ*), and S0. In combination with MS-CASPT2 calculated linearly interpolated internal coordinate paths, the photophysical mechanism of 6SeGua has been proposed. The initially populated S2(1ππ*) state decays to either S1(1 nπ*) or T2(3 nπ*) states through a three-state S2/S1/T2 intersection point. The large S2/T2 spin-orbit coupling of 435 cm-1, according to the classical El-Sayed rule, benefits the S2 → T2 intersystem crossing process. The S1(1 nπ*) state that stems from the S2 → S1 internal conversion process at the S2/S1/T2 intersection point can further jump to the T2(3 nπ*) state through the S1 → T2 intersystem crossing process. This process does not comply with the El-Sayed rule, but it is still related to a comparatively large spin-orbit coupling of 39 cm-1 and is expected to occur relatively fast. Finally, the T2(3 nπ*) state, which is populated from the above S2 → T2 and S1 → T2 intersystem crossing processes, decays to the T1(3ππ*) state via an internal conversion process. Because there is merely a small energy barrier of 0.11 eV separating the T1(3ππ*) minimum and an energetically allowed two-state T1/S0 intersection point, the T1(3ππ*) state still can decay to the S0 state quickly, which is also enhanced by a large T1/S0 spin-orbit coupling of 252 cm-1. Our proposed mechanism explains experimentally observed ultrafast intersystem crossing processes in 6SeGua and its 835-fold acceleration of the T1 state decay to the S0 state compared with 6tGua. Finally, we have found that the ground-state electronic structure of 6SeGua has more apparent multireference character.
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12
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Wu X, Ehrmaier J, Sobolewski AL, Karsili TNV, Domcke W. Mechanisms of photoreactivity in hydrogen-bonded adenine-H 2O complexes. Phys Chem Chem Phys 2019; 21:14238-14249. [PMID: 30543228 DOI: 10.1039/c8cp05305g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The mechanisms of photoinduced reactions of adenine with water molecules in hydrogen-bonded adenine-water complexes were investigated with ab initio wave-function-based electronic-structure calculations. Two excited-state electron/proton transfer reaction mechanisms have been characterized: H-atom abstraction from water by photoexcited adenine as well as H-atom transfer from photoexcited adenine or the (adenine+H) radical to water. In the water-to-adenine H-atom transfer reaction, an electron from one of the p orbitals of the water molecule fills the hole in the n (π) orbital of the nπ* (ππ*) excited state of adenine, resulting in a charge-separated electronic state. The electronic charge separation is neutralized by the transfer of a proton from the water molecule to adenine, resulting in the (adenine+H)OH biradical in the electronic ground state. In the adenine-to-water H-atom transfer reaction, πσ* states localized at the acidic sites of adenine provide the mechanism for the photoejection of an electron from adenine, which is followed by proton transfer to the hydrogen-bonded water molecule, resulting in the (adenine-H)H3O biradical. The energy profiles of the photoreactions have been computed as relaxed scans with the ADC(2) electronic-structure method. These reactions, which involve the reactivity of adenine with hydrogen-bonded water molecules, compete with the well-established intrinsic excited-state deactivation mechanisms of adenine via ring-puckering or ring-opening conical intersections. By providing additional decay channels, the electron/proton exchange reactions with water can account for the observed significantly shortened excited-state lifetime of adenine in aqueous environments. These findings indicate that adenine possibly was not only a photostabilizer at the beginning of life, but also a primordial photocatalyst for water splitting.
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Affiliation(s)
- Xiuxiu Wu
- Department of Chemistry, Technical University of Munich, D-85747 Garching, Germany.
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13
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Martínez-Fernández L, Arslancan S, Ivashchenko D, Crespo-Hernández CE, Corral I. Tracking the origin of photostability in purine nucleobases: the photophysics of 2-oxopurine. Phys Chem Chem Phys 2019; 21:13467-13473. [DOI: 10.1039/c9cp00879a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Molding purine PES through functionalization: whilst purine C2-substitution maintains the features of the spectroscopic PES of the heterocycle, C6-functionalization reshapes its topography leading to photostable systems.
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Affiliation(s)
| | - Serra Arslancan
- Departamento de Química
- Universidad Autónoma de Madrid
- 28049 Madrid
- Spain
| | - Dmytro Ivashchenko
- Departamento de Química
- Universidad Autónoma de Madrid
- 28049 Madrid
- Spain
- Departamento de Química e Bioquímica
| | | | - Inés Corral
- Departamento de Química
- Universidad Autónoma de Madrid
- 28049 Madrid
- Spain
- IADCHEM
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14
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Stange UC, Temps F. Ultrafast electronic deactivation of UV-excited adenine and its ribo- and deoxyribonucleosides and -nucleotides: A comparative study. Chem Phys 2018. [DOI: 10.1016/j.chemphys.2018.08.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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15
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Williams HL, Erickson BA, Neumark DM. Time-resolved photoelectron spectroscopy of adenosine and adenosine monophosphate photodeactivation dynamics in water microjets. J Chem Phys 2018; 148:194303. [PMID: 30307253 DOI: 10.1063/1.5027258] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The excited state relaxation dynamics of adenosine and adenosine monophosphate were studied at multiple excitation energies using femtosecond time-resolved photoelectron spectroscopy in a liquid water microjet. At pump energies of 4.69-4.97 eV, the lowest ππ* excited state, S1, was accessed and its decay dynamics were probed via ionization at 6.20 eV. By reversing the role of the pump and probe lasers, a higher-lying ππ* state was excited at 6.20 eV and its time-evolving photoelectron spectrum was monitored at probe energies of 4.69-4.97 eV. The S1 ππ* excited state was found to decay with a lifetime ranging from ∼210 to 250 fs in adenosine and ∼220 to 250 fs in adenosine monophosphate. This lifetime drops with increasing pump photon energy. Signal from the higher-lying ππ* excited state decayed on a time scale of ∼320 fs and was measureable only in adenosine monophosphate.
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Affiliation(s)
- Holly L Williams
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Blake A Erickson
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Daniel M Neumark
- Department of Chemistry, University of California, Berkeley, California 94720, USA
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16
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Marchetti B, Karsili TNV, Ashfold MNR, Domcke W. A 'bottom up', ab initio computational approach to understanding fundamental photophysical processes in nitrogen containing heterocycles, DNA bases and base pairs. Phys Chem Chem Phys 2018; 18:20007-27. [PMID: 26980149 DOI: 10.1039/c6cp00165c] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The availability of non-radiative decay mechanisms by which photoexcited molecules can revert to their ground electronic state, without experiencing potentially deleterious chemical transformation, is fundamental to molecular photostability. This Perspective Article combines results of new ab initio electronic structure calculations and prior experimental data in an effort to systematise trends in the non-radiative decay following UV excitation of selected families of heterocyclic molecules. We start with the prototypical uni- and bicyclic molecules phenol and indole, and explore the structural and photophysical consequences of incorporating progressively more nitrogen atoms within the respective ring structures en route to the DNA bases thymine, cytosine, adenine and guanine. For each of the latter, we identify low energy non-radiative decay pathways via conical intersections with the ground state potential energy surface accessed by out-of-plane ring deformations. This is followed by summary descriptions and illustrations of selected rival (electron driven H atom transfer) non-radiative excited state decay processes that demand consideration once the nucleobases are merely components in larger biomolecular systems like nucleosides, and both individual and stacked base-pairs.
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Affiliation(s)
- Barbara Marchetti
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
| | - Tolga N V Karsili
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK. and Department of Chemistry, Technische Universität München, Lichtenbergstr. 4, 85748 Garching, Germany
| | - Michael N R Ashfold
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
| | - Wolfgang Domcke
- Department of Chemistry, Technische Universität München, Lichtenbergstr. 4, 85748 Garching, Germany
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17
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Mondal S, Puranik M. Sub-50 fs excited state dynamics of 6-chloroguanine upon deep ultraviolet excitation. Phys Chem Chem Phys 2017; 18:13874-87. [PMID: 27146198 DOI: 10.1039/c6cp01746k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The photophysical properties of natural nucleobases and their respective nucleotides are ascribed to the sub-picosecond lifetime of their first singlet states in the UV-B region (260-350 nm). Electronic transitions of the ππ* type, which are stronger than those in the UV-B region, lie at the red edge of the UV-C range (100-260 nm) in all isolated nucleobases. The lowest energetic excited states in the UV-B region of nucleobases have been investigated using a plethora of experimental and theoretical methods in gas and solution phases. The sub-picosecond lifetime of these molecules is not a general attribute of all nucleobases but specific to the five primary nucleobases and a few xanthine and methylated derivatives. To determine the overall UV photostability, we aim to understand the effect of more energetic photons lying in the UV-C region on nucleobases. To determine the UV-C initiated photophysics of a nucleobase system, we chose a halogen substituted purine, 6-chloroguanine (6-ClG), that we had investigated previously using resonance Raman spectroscopy. We have performed quantitative measurements of the resonance Raman cross-section across the Bb absorption band (210-230 nm) and constructed the Raman excitation profiles. We modeled the excitation profiles using Lee and Heller's time-dependent theory of resonance Raman intensities to extract the initial excited state dynamics of 6-ClG within 30-50 fs after photoexcitation. We found that imidazole and pyrimidine rings of 6-ClG undergo expansion and contraction, respectively, following photoexcitation to the Bb state. The amount of distortions of the excited state structure from that of the ground state structure is reflected by the total internal reorganization energy that is determined at 112 cm(-1). The contribution of the inertial component of the solvent response towards the total reorganization energy was obtained at 1220 cm(-1). In addition, our simulation also yields an instantaneous response of the first solvation shell within an ultrafast timescale of less than 30 fs following photoexcitation.
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Affiliation(s)
- Sayan Mondal
- Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune 411008, India.
| | - Mrinalini Puranik
- Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune 411008, India.
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18
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Mondal S, Puranik M. Ultrafast structural dynamics of photoexcited adenine. Phys Chem Chem Phys 2017; 19:20224-20240. [DOI: 10.1039/c7cp03092d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Ultraviolet Resonance Raman (UVRR) spectroscopy derives distinct electronic properties of adenine in the La (260 nm) and Bb (210 nm) excited states.
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Affiliation(s)
- Sayan Mondal
- Indian Institute of Science Education and Research
- Pune – 411008
- India
| | - Mrinalini Puranik
- Indian Institute of Science Education and Research
- Pune – 411008
- India
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19
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Li Q, Giussani A, Segarra-Martí J, Nenov A, Rivalta I, Voityuk AA, Mukamel S, Roca-Sanjuán D, Garavelli M, Blancafort L. Multiple Decay Mechanisms and 2D-UV Spectroscopic Fingerprints of Singlet Excited Solvated Adenine-Uracil Monophosphate. Chemistry 2016; 22:7497-507. [PMID: 27113273 PMCID: PMC5021121 DOI: 10.1002/chem.201505086] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Indexed: 02/04/2023]
Abstract
The decay channels of singlet excited adenine uracil monophosphate (ApU) in water are studied with CASPT2//CASSCF:MM potential energy calculations and simulation of the 2D-UV spectroscopic fingerprints with the aim of elucidating the role of the different electronic states of the stacked conformer in the excited state dynamics. The adenine (1) La state can decay without a barrier to a conical intersection with the ground state. In contrast, the adenine (1) Lb and uracil S(U) states have minima that are separated from the intersections by sizeable barriers. Depending on the backbone conformation, the CT state can undergo inter-base hydrogen transfer and decay to the ground state through a conical intersection, or it can yield a long-lived minimum stabilized by a hydrogen bond between the two ribose rings. This suggests that the (1) Lb , S(U) and CT states of the stacked conformer may all contribute to the experimental lifetimes of 18 and 240 ps. We have also simulated the time evolution of the 2D-UV spectra and provide the specific fingerprint of each species in a recommended probe window between 25 000 and 38 000 cm(-1) in which decongested, clearly distinguishable spectra can be obtained. This is expected to allow the mechanistic scenarios to be discerned in the near future with the help of the corresponding experiments. Our results reveal the complexity of the photophysics of the relatively small ApU system, and the potential of 2D-UV spectroscopy to disentangle the photophysics of multichromophoric systems.
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Affiliation(s)
- Quansong Li
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 100081, Beijing, P.R. China
| | - Angelo Giussani
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126, Bologna, Italy
| | - Javier Segarra-Martí
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126, Bologna, Italy
| | - Artur Nenov
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126, Bologna, Italy
| | - Ivan Rivalta
- Univ Lyon, >Ens de Lyon, CNRS, Université Lyon 1, Laboratoire de Chimie UMR 5182, 69342, Lyon, France
| | - Alexander A Voityuk
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, Campus de Montilvi, 17071, Girona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010, Barcelona, Spain
| | - Shaul Mukamel
- Department of Chemistry, University of California, Irvine, California, 92697-2025, USA
| | - Daniel Roca-Sanjuán
- Instituto de Ciencia Molecular, Universitat de València, P. O. Box 22085, 46071, Valencia, Spain
| | - Marco Garavelli
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126, Bologna, Italy.
- Univ Lyon, >Ens de Lyon, CNRS, Université Lyon 1, Laboratoire de Chimie UMR 5182, 69342, Lyon, France.
| | - Lluís Blancafort
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, Campus de Montilvi, 17071, Girona, Spain.
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20
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Stavros VG, Verlet JRR. Gas-Phase Femtosecond Particle Spectroscopy: A Bottom-Up Approach to Nucleotide Dynamics. Annu Rev Phys Chem 2016; 67:211-32. [PMID: 26980306 DOI: 10.1146/annurev-physchem-040215-112428] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We summarize how gas-phase ultrafast charged-particle spectroscopy has been used to provide an understanding of the photophysics of DNA building blocks. We focus on adenine and discuss how, following UV excitation, specific interactions determine the fates of its excited states. The dynamics can be probed using a systematic bottom-up approach that provides control over these interactions and that allows ever-larger complexes to be studied. Starting from a chromophore in adenine, the excited state decay mechanisms of adenine and chemically substituted or clustered adenine are considered and then extended to adenosine mono-, di-, and trinucleotides. We show that the gas-phase approach can offer exquisite insight into the dynamics observed in aqueous solution, but we also highlight stark differences. An outlook is provided that discusses some of the most promising developments in this bottom-up approach.
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Affiliation(s)
- Vasilios G Stavros
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, United Kingdom;
| | - Jan R R Verlet
- Department of Chemistry, University of Durham, Durham, DH1 3LE, United Kingdom;
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21
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Improta R, Santoro F, Blancafort L. Quantum Mechanical Studies on the Photophysics and the Photochemistry of Nucleic Acids and Nucleobases. Chem Rev 2016; 116:3540-93. [PMID: 26928320 DOI: 10.1021/acs.chemrev.5b00444] [Citation(s) in RCA: 338] [Impact Index Per Article: 42.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The photophysics and photochemistry of DNA is of great importance due to the potential damage of the genetic code by UV light. Quantum mechanical studies have played a key role in interpretating the results of modern time-resolved pump-probe spectroscopy, and in elucidating the main photoactivated reactive paths. This review provides a concise, complete picture of the computational studies carried out, approximately, in the past decade. We start with an overview of the photophysics of the nucleobases in the gas phase and in solution. We discuss the proposed mechanisms for ultrafast decay to the ground state, that involve conical intersections, consider the role of triplet states, and analyze how the solvent modulates the photophysics. Then we move to larger systems, from dinucleotides to single- and double-stranded oligonucleotides. We focus on the possible role of charge transfer and delocalized or excitonic states in the photophysics of these systems and discuss the main photochemical paths. We finish with an outlook on the current challenges in the field and future directions of research.
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Affiliation(s)
- Roberto Improta
- Istituto di Biostrutture Biommagini (IBB-CNR), CNR-Consiglio Nazionale delle Ricerche , Via Mezzocannone 16, I-80134, Napoli, Italy
| | - Fabrizio Santoro
- Area della Ricerca di Pisa, Istituto di Chimica dei Composti Organo Metallici (ICCOM-CNR), CNR-Consiglio Nazionale delle Ricerche , Via G. Moruzzi 1, I-56124 Pisa, Italy
| | - Lluís Blancafort
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, Campus de Montilivi , 17071 Girona, Spain
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22
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Wu X, Karsili TNV, Domcke W. Excited-State Deactivation of Adenine by Electron-Driven Proton-Transfer Reactions in Adenine-Water Clusters: A Computational Study. Chemphyschem 2016; 17:1298-304. [DOI: 10.1002/cphc.201501154] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Xiuxiu Wu
- Department of Chemistry; Technische Universität München; 85747 Garching Germany
| | - Tolga N. V. Karsili
- Department of Chemistry; Technische Universität München; 85747 Garching Germany
| | - Wolfgang Domcke
- Department of Chemistry; Technische Universität München; 85747 Garching Germany
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23
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González-Luque R, Climent T, González-Ramírez I, Merchán M, Serrano-Andrés L. Singlet-Triplet States Interaction Regions in DNA/RNA Nucleobase Hypersurfaces. J Chem Theory Comput 2015; 6:2103-14. [PMID: 26615938 DOI: 10.1021/ct100164m] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The present study provides new insight into the intrinsic mechanisms for the population of the triplet manifold in DNA nucleobases by determining, at the multiconfigurational CASSCF/CASPT2 level, the singlet-triplet states crossing regions and the main decay paths for their lowest singlet and triplet states after near-UV irradiation. The studied singlet-triplet interacting regions are accessible along the minimum energy path of the initially populated singlet bright (1)ππ* state. In particular, all five natural DNA/RNA nucleobases have, at the end of the main minimum energy path and near a conical intersection of the ground and (1)ππ* states, a low-energy, easily accessible, singlet-triplet crossing region directly connecting the lowest singlet and triplet ππ* excited states. Adenine, thymine, and uracil display additional higher-energy crossing regions related to the presence of low-lying singlet and a triplet nπ* state. These funnels are absent in guanine and cytosine, which have the bright (1)ππ* state lower in energy and less accessible nπ* states. Knowledge of the location and accessibility of these regions, in which the singlet-triplet interaction is related to large spin-orbit coupling elements, may help to understand experimental evidence such as the wavelength dependence measured for the triplet formation quantum yield in nucleobases and the prevalence of adenine and thymine components in the phosphorescence spectra of DNA.
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Affiliation(s)
- Remedios González-Luque
- Instituto de Ciencia Molecular, Universitat de València, Apartado 22085, ES-46071 Valencia, Spain
| | - Teresa Climent
- Instituto de Ciencia Molecular, Universitat de València, Apartado 22085, ES-46071 Valencia, Spain
| | - Israel González-Ramírez
- Instituto de Ciencia Molecular, Universitat de València, Apartado 22085, ES-46071 Valencia, Spain
| | - Manuela Merchán
- Instituto de Ciencia Molecular, Universitat de València, Apartado 22085, ES-46071 Valencia, Spain
| | - Luis Serrano-Andrés
- Instituto de Ciencia Molecular, Universitat de València, Apartado 22085, ES-46071 Valencia, Spain
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24
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Chaiwongwattana S, Sapunar M, Ponzi A, Decleva P, Došlić N. Exploration of Excited State Deactivation Pathways of Adenine Monohydrates. J Phys Chem A 2015; 119:10637-44. [DOI: 10.1021/acs.jpca.5b07496] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
| | - Marin Sapunar
- Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Aurora Ponzi
- Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Piero Decleva
- Dipartimento di
Scienze Chimiche, Università di Trieste, 34127 Trieste, Italy
| | - Nađa Došlić
- Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
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25
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Nenov A, Segarra-Martí J, Giussani A, Conti I, Rivalta I, Dumont E, Jaiswal VK, Altavilla SF, Mukamel S, Garavelli M. Probing deactivation pathways of DNA nucleobases by two-dimensional electronic spectroscopy: first principles simulations. Faraday Discuss 2015; 177:345-62. [PMID: 25607949 DOI: 10.1039/c4fd00175c] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The SOS//QM/MM [Rivalta et al., Int. J. Quant. Chem., 2014, 114, 85] method consists of an arsenal of computational tools allowing accurate simulation of one-dimensional (1D) and bi-dimensional (2D) electronic spectra of monomeric and dimeric systems with unprecedented details and accuracy. Prominent features like doubly excited local and excimer states, accessible in multi-photon processes, as well as charge-transfer states arise naturally through the fully quantum-mechanical description of the aggregates. In this contribution the SOS//QM/MM approach is extended to simulate time-resolved 2D spectra that can be used to characterize ultrafast excited state relaxation dynamics with atomistic details. We demonstrate how critical structures on the excited state potential energy surface, obtained through state-of-the-art quantum chemical computations, can be used as snapshots of the excited state relaxation dynamics to generate spectral fingerprints for different de-excitation channels. The approach is based on high-level multi-configurational wavefunction methods combined with non-linear response theory and incorporates the effects of the solvent/environment through hybrid quantum mechanics/molecular mechanics (QM/MM) techniques. Specifically, the protocol makes use of the second-order Perturbation Theory (CASPT2) on top of Complete Active Space Self Consistent Field (CASSCF) strategy to compute the high-lying excited states that can be accessed in different 2D experimental setups. As an example, the photophysics of the stacked adenine-adenine dimer in a double-stranded DNA is modeled through 2D near-ultraviolet (NUV) spectroscopy.
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Affiliation(s)
- Artur Nenov
- Dipartimento di Chimica G. Ciamician, Università di Bologna, Via F. Selmi 2, 40126 Bologna, Italy.
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26
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Altavilla SF, Segarra-Martí J, Nenov A, Conti I, Rivalta I, Garavelli M. Deciphering the photochemical mechanisms describing the UV-induced processes occurring in solvated guanine monophosphate. Front Chem 2015; 3:29. [PMID: 25941671 PMCID: PMC4403598 DOI: 10.3389/fchem.2015.00029] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 03/30/2015] [Indexed: 01/17/2023] Open
Abstract
The photophysics and photochemistry of water-solvated guanine monophosphate (GMP) are here characterized by means of a multireference quantum-chemical/molecular mechanics theoretical approach (CASPT2//CASSCF/AMBER) in order to elucidate the main photo-processes occurring upon UV-light irradiation. The effect of the solvent and of the phosphate group on the energetics and structural features of this system are evaluated for the first time employing high-level ab initio methods and thoroughly compared to those in vacuo previously reported in the literature and to the experimental evidence to assess to which extent they influence the photoinduced mechanisms. Solvated electronic excitation energies of solvated GMP at the Franck-Condon (FC) region show a red shift for the ππ(*) La and Lb states, whereas the energy of the oxygen lone-pair nπ(*) state is blue-shifted. The main photoinduced decay route is promoted through a ring-puckering motion along the bright lowest-lying La state toward a conical intersection (CI) with the ground state, involving a very shallow stationary point along the minimum energy pathway in contrast to the barrierless profile found in gas-phase, the point being placed at the end of the minimum energy path (MEP) thus endorsing its ultrafast deactivation in accordance with time-resolved transient and photoelectron spectroscopy experiments. The role of the nπ(*) state in the solvated system is severely diminished as the crossings with the initially populated La state and also with the Lb state are placed too high energetically to partake prominently in the deactivation photo-process. The proposed mechanism present in solvated and in vacuo DNA/RNA chromophores validates the intrinsic photostability mechanism through CI-mediated non-radiative processes accompanying the bright excited-state population toward the ground state and subsequent relaxation back to the FC region.
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Affiliation(s)
| | | | - Artur Nenov
- Dipartimento di Chimica “G. Ciamician,” Università di BolognaBologna, Italy
| | - Irene Conti
- Dipartimento di Chimica “G. Ciamician,” Università di BolognaBologna, Italy
| | - Ivan Rivalta
- École Normale Supérieure de Lyon, Centre National de la Recherche Scientifique, UMR 5182, Université de LyonLyon, France
| | - Marco Garavelli
- Dipartimento di Chimica “G. Ciamician,” Università di BolognaBologna, Italy
- École Normale Supérieure de Lyon, Centre National de la Recherche Scientifique, UMR 5182, Université de LyonLyon, France
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27
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Computational modeling of photoexcitation in DNA single and double strands. Top Curr Chem (Cham) 2015; 356:89-122. [PMID: 24647841 DOI: 10.1007/128_2014_533] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The photoexcitation of DNA strands triggers extremely complex photoinduced processes, which cannot be understood solely on the basis of the behavior of the nucleobase building blocks. Decisive factors in DNA oligomers and polymers include collective electronic effects, excitonic coupling, hydrogen-bonding interactions, local steric hindrance, charge transfer, and environmental and solvent effects. This chapter surveys recent theoretical and computational efforts to model real-world excited-state DNA strands using a variety of established and emerging theoretical methods. One central issue is the role of localized vs delocalized excitations and the extent to which they determine the nature and the temporal evolution of the initial photoexcitation in DNA strands.
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28
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Conti I, Nenov A, Höfinger S, Flavio Altavilla S, Rivalta I, Dumont E, Orlandi G, Garavelli M. Excited state evolution of DNA stacked adenines resolved at the CASPT2//CASSCF/Amber level: from the bright to the excimer state and back. Phys Chem Chem Phys 2015; 17:7291-302. [DOI: 10.1039/c4cp05546b] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
La and excimer state population exchange, along the common puckering decay coordinate, explains the longest DNA lifetime component.
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Affiliation(s)
- Irene Conti
- Dipartimento di Chimica “G. Ciamician”
- Università di Bologna
- Bologna, Italy
| | - Artur Nenov
- Dipartimento di Chimica “G. Ciamician”
- Università di Bologna
- Bologna, Italy
| | - Siegfried Höfinger
- Zentraler Informatikdienst
- Technische Universität Wien
- 1040 Wien, Austria
- Department of Physics
- Michigan Technological University
| | | | - Ivan Rivalta
- Université de Lyon
- CNRS
- Institut de Chimie de Lyon
- École Normale Supérieure de Lyon
- F-69364 Lyon Cedex 07, France
| | - Elise Dumont
- Laboratoire de Chimie
- Ecole Normale Supérieure de Lyon
- Lyon, France
| | - Giorgio Orlandi
- Dipartimento di Chimica “G. Ciamician”
- Università di Bologna
- Bologna, Italy
| | - Marco Garavelli
- Dipartimento di Chimica “G. Ciamician”
- Università di Bologna
- Bologna, Italy
- Laboratoire de Chimie
- Ecole Normale Supérieure de Lyon
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29
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Roberts GM, Marroux HJB, Grubb MP, Ashfold MNR, Orr-Ewing AJ. On the Participation of Photoinduced N–H Bond Fission in Aqueous Adenine at 266 and 220 nm: A Combined Ultrafast Transient Electronic and Vibrational Absorption Spectroscopy Study. J Phys Chem A 2014; 118:11211-25. [DOI: 10.1021/jp508501w] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gareth M. Roberts
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Hugo J. B. Marroux
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Michael P. Grubb
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Michael N. R. Ashfold
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Andrew J. Orr-Ewing
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
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30
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Chen X, Fang W, Wang H. Slow deactivation channels in UV-photoexcited adenine DNA. Phys Chem Chem Phys 2014; 16:4210-9. [PMID: 24452764 DOI: 10.1039/c3cp55020f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The molecular mechanism for removing the excess energy in DNA bases is responsible for the high photostability of DNA and is thus the subject of intense theoretical/computational investigation. To understand why the excited state decay of the stacked bases is significantly longer than that of the monomers, we carried out electronic structure calculations on an adenine monomer and an aqueous (dA)5 oligonucleotide employing the CASPT2//CASSCF and CASPT2//CASSCF/AMBER levels of theory. The newly-found bright excited state pair Sstack1((1)ππ*) and Sstack2((1)ππ*) of d(A)5, originated from base stacking, is of intra-base charge transfer nature and occurs in different stacked bases with charge transfer along opposite directions. Two slow deactivation channels of d(A)5 were proposed as a result of the sizable barriers along the relaxation paths starting from the FC point of the Sstack1((1)ππ*) state. The SN1P((1)nπ*) state of d(A)5 serves as an intermediate state in one relaxation channel, to which a nonadiabatic decay from the Sstack1((1)ππ*) state occurs in an energy degeneracy region. A relatively high barrier in this state is found and attributed to the steric hindrance of the DNA environment due to the large NH2 group twisting, which gives a weak and red-shifted fluorescence. Another direct relaxation channel, induced by the C2-H2 bond twisting motion, is found to go through a conical intersection between the Sstack1((1)ππ*) and the ground state. The barrier found here enables fluorescence from the Sstack1((1)ππ*) state and may explain the bright state emission observed in the fluorescence upconversion measurements. The inter-molecular SCT((1)ππ*) state may be involved in the slow relaxation process of the photoexcited adenine oligomers through efficient internal conversion to the intra-base Sstack1((1)ππ*) state.
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Affiliation(s)
- Xuebo Chen
- Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education, Department of Chemistry, Beijing Normal University, Xin-wai-da-jie No. 19, Beijing, 100875, China.
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31
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Zhang Y, Improta R, Kohler B. Mode-specific vibrational relaxation of photoexcited guanosine 5'-monophosphate and its acid form: a femtosecond broadband mid-IR transient absorption and theoretical study. Phys Chem Chem Phys 2014; 16:1487-99. [PMID: 24302276 DOI: 10.1039/c3cp53815j] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
UV-pump/broadband-mid-IR-probe transient absorption (TA) experiments and ab initio quantum mechanical (QM) calculations were used to investigate the photophysics in heavy water of the neutral and acid forms of guanosine 5'-monophosphate (GMP and GMPD(+), respectively). Excited GMP undergoes ultrafast internal conversion (IC) and returns to the electronic ground state in less than one picosecond with a large amount of excess vibrational energy. The spectroscopic signals are dominated by vibrational cooling - a process in which the solute dissipates vibrational energy to the solvent. For neutral GMP, cooling proceeds with a time constant of 3 ps. Following IC, at least some medium-frequency modes such as the carbonyl stretch and an in-plane ring vibration are excited, suggesting that the vibrational energy distribution is non-statistical. This is consistent with predicted structural changes upon passage through the S1/S0 conical intersection. GMPD(+) differs from GMP by a single deuteron at the N7 position, but has a dramatically longer lifetime of 200 ps. Vibrational cooling of the S1 state of GMPD(+) was monitored via several medium-frequency modes that were assigned using QM calculations. These medium-frequency modes are also vibrationally excited in a non-statistical fashion. Excitation of these modes is in line with the change in geometry at the S1 minimum of GMPD(+) predicted by QM calculations. Furthermore, these modes relax at different rates, fully consistent with QM calculations, which predict that excited vibrational states of the carbonyl stretch couple strongly to the D2O solvent and thus deactivate via intermolecular energy transfer (IET). In contrast, the ring stretch couples strongly to other ring modes of the guanine chromophore and appears to decay via intramolecular vibrational energy redistribution (IVR).
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Affiliation(s)
- Yuyuan Zhang
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59715, USA.
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Benda Z, Szalay PG. Details of the Excited-State Potential Energy Surfaces of Adenine by Coupled Cluster Techniques. J Phys Chem A 2014; 118:6197-207. [DOI: 10.1021/jp505331s] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Zsuzsanna Benda
- Laboratory of Theoretical Chemistry, Institute of Chemistry, Eötvös University, P.O. Box 32, H-1518 Budapest, Hungary
| | - Péter G. Szalay
- Laboratory of Theoretical Chemistry, Institute of Chemistry, Eötvös University, P.O. Box 32, H-1518 Budapest, Hungary
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33
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Barbatti M. Photorelaxation Induced by Water–Chromophore Electron Transfer. J Am Chem Soc 2014; 136:10246-9. [DOI: 10.1021/ja505387c] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Mario Barbatti
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz
1, D-45470 Mülheim
an der Ruhr, Germany
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34
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Chatterley AS, West CW, Roberts GM, Stavros VG, Verlet JRR. Mapping the Ultrafast Dynamics of Adenine onto Its Nucleotide and Oligonucleotides by Time-Resolved Photoelectron Imaging. J Phys Chem Lett 2014; 5:843-848. [PMID: 26274076 DOI: 10.1021/jz500264c] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The intrinsic photophysics of nucleobases and nucleotides following UV absorption presents a key reductionist step toward understanding the complex photodamage mechanisms occurring in DNA. The decay mechanism of adenine in particular has been the focus of intense investigation, as has how these correlate to those of its more biologically relevant nucleotide and oligonucleotides in aqueous solution. Here, we report on time-resolved photoelectron imaging of the deprotonated 3'-deoxy-adenosine-5'-monophosphate nucleotide and the adenosine di- and trinucleotides. Through a comparison of gas- and solution-phase experiments and available theoretical studies, the dynamics of the base are shown to be relatively insensitive to the surrounding environment. The decay mechanism primarily involves internal conversion from the initially populated (1)ππ* states to the ground state. The relaxation dynamics of the adenosine oligonucleotides are similar to those of the nucleobase, in contrast to the aqueous oligonucleotides, where a fraction of the ensemble forms long-lived excimer states.
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Affiliation(s)
- Adam S Chatterley
- †Department of Chemistry, University of Durham, Durham DH1 3LE, United Kingdom
- ‡Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Christopher W West
- †Department of Chemistry, University of Durham, Durham DH1 3LE, United Kingdom
| | - Gareth M Roberts
- ‡Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Vasilios G Stavros
- ‡Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Jan R R Verlet
- †Department of Chemistry, University of Durham, Durham DH1 3LE, United Kingdom
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Chatterley AS, West CW, Stavros VG, Verlet JRR. Time-resolved photoelectron imaging of the isolated deprotonated nucleotides. Chem Sci 2014. [DOI: 10.1039/c4sc01493f] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Time-resolved photoelectron spectroscopy of deprotonated nucleotides provides new insights into their relaxation dynamics.
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Affiliation(s)
- Adam S. Chatterley
- Department
- of Chemistry
- University of Durham
- Durham DH1 3LE, United Kingdom
- Department of Chemistry
| | | | - Vasilios G. Stavros
- Department of Chemistry
- University of Warwick
- Coventry CV4 7AL, United Kingdom
| | - Jan R. R. Verlet
- Department
- of Chemistry
- University of Durham
- Durham DH1 3LE, United Kingdom
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36
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Photochemistry of Nucleic Acid Bases and Their Thio- and Aza-Analogues in Solution. Top Curr Chem (Cham) 2014; 355:245-327. [DOI: 10.1007/128_2014_554] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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37
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Excited States Behavior of Nucleobases in Solution: Insights from Computational Studies. Top Curr Chem (Cham) 2014; 355:329-57. [DOI: 10.1007/128_2013_524] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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38
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Miyazaki M, Kang H, Choi CM, Han NS, Song JK, Kim NJ, Fujii M. MODE-specific deactivation of adenine at the singlet excited states. J Chem Phys 2013; 139:124311. [DOI: 10.1063/1.4821830] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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39
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Stuhldreier MC, Temps F. Ultrafast photo-initiated molecular quantum dynamics in the DNA dinucleotide d(ApG) revealed by broadband transient absorption spectroscopy. Faraday Discuss 2013; 163:173-88; discussion 243-75. [PMID: 24020202 DOI: 10.1039/c3fd00003f] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The ultrafast photo-initiated quantum dynamics of the adenine-guanine dinucleotide d(ApG) in aqueous solution (pH 7) has been studied by femtosecond time-resolved spectroscopy after excitation at lambda = 260 nm. The results reveal a hierarchy of processes on time scales from tau < 100 fs to tau > 100 ps. Characteristic spectro-temporal signatures are observed indicating the transformation of the molecules in the electronic relaxation from the photo-excited state to a long-lived exciplex. In particular, broadband UV/VIS excited-state absorption (ESA) measurements detected a distinctive absorption by the excited dinucleotide around lambda = 335 nm, approximately 0.5 eV to the blue compared to the maximum of the broad and unstructured ESA spectrum after excitation of an equimolar mixture of the mononucleotides dAMP and dGMP. A similar feature has been identified as signature of the excimer in the dynamics of the adenine dinucleotide d(ApA). The lifetime of the d(ApG) exciplex was found to be tau = 124 +/- 4 ps both from the ESA decay time and from the ground-state recovery time, far longer than the sub-picosecond lifetimes of excited dAMP or dGMP. Fluorescence-time profiles measured by the up-conversion technique indicate that the exciplex state is reached around approximately 6 ps after excitation. Very weak residual fluorescence at longer times red-shifted to the emission from the photo-excited state shows that the exciplex is almost optically dark, but still has enough oscillator strength to give rise to the dual fluorescence of the dinucleotide in the static fluorescence spectrum.
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Affiliation(s)
- Mayra C Stuhldreier
- Institute of Physical Chemistry, Christian-Albrechts-University Kiel, Olshausenstr. 40, D-24098 Kiel, Germany
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40
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Banyasz A, Gustavsson T, Onidas D, Changenet-Barret P, Markovitsi D, Improta R. Multi-Pathway Excited State Relaxation of Adenine Oligomers in Aqueous Solution: A Joint Theoretical and Experimental Study. Chemistry 2013; 19:3762-74. [DOI: 10.1002/chem.201202741] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2012] [Revised: 12/11/2012] [Indexed: 11/09/2022]
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41
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Gustavsson T, Sarkar N, Vayá I, Jiménez MC, Markovitsi D, Improta R. A joint experimental/theoretical study of the ultrafast excited state deactivation of deoxyadenosine and 9-methyladenine in water and acetonitrile. Photochem Photobiol Sci 2013; 12:1375-86. [DOI: 10.1039/c3pp50060h] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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42
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Picconi D, Avila Ferrer FJ, Improta R, Lami A, Santoro F. Quantum-classical effective-modes dynamics of the ππ* → nπ* decay in 9H-adenine. A quadratic vibronic coupling model. Faraday Discuss 2013; 163:223-42; discussion 243-75. [DOI: 10.1039/c3fd20147c] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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43
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Engler G, Seefeld K, Schmitt M, Tatchen J, Grotkopp O, Müller TJJ, Kleinermanns K. Acetylation makes the difference: a joint experimental and theoretical study on low-lying electronically excited states of 9H-adenine and 9-acetyladenine. Phys Chem Chem Phys 2013; 15:1025-31. [DOI: 10.1039/c2cp42859h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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44
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Excitation of Nucleobases from a Computational Perspective I: Reaction Paths. Top Curr Chem (Cham) 2013; 355:57-97. [DOI: 10.1007/128_2013_501] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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45
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Cui PY, Liu BP, Yan S. DFT investigation on the double hydrogen-bonded system: The oxidation and hydration effect. J STRUCT CHEM+ 2012. [DOI: 10.1134/s0022476612050204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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46
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Caruso P, Causà M, Cimino P, Crescenzi O, D’Amore M, Improta R, Pavone M, Rega N. Effects of molecular dynamics and solvation on the electronic structure of molecular probes. Theor Chem Acc 2012. [DOI: 10.1007/s00214-012-1211-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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47
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48
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Tseng CH, Sándor P, Kotur M, Weinacht TC, Matsika S. Two-dimensional fourier transform spectroscopy of adenine and uracil using shaped ultrafast laser pulses in the deep UV. J Phys Chem A 2011; 116:2654-61. [PMID: 22074393 DOI: 10.1021/jp207228b] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
We compare two-dimensional (2D) ultrafast Fourier transform spectroscopy measurements in the deep UV (262 nm) for adenine and uracil in solution. Both molecules show excited-state absorption on short time scales and ground-state bleaching extending for over 1 ps. While the 2D spectrum for uracil shows changes in the center of gravity during the first few hundred femtoseconds, the center of gravity of the 2D spectrum for adenine does not show similar changes. We discuss our results in light of ab initio electronic structure calculations.
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Affiliation(s)
- Chien-hung Tseng
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, USA
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49
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Roca-Sanjuán D, Aquilante F, Lindh R. Multiconfiguration second-order perturbation theory approach to strong electron correlation in chemistry and photochemistry. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2011. [DOI: 10.1002/wcms.97] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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50
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Giussani A, Merchán M, Roca-Sanjuán D, Lindh R. Essential on the Photophysics and Photochemistry of the Indole Chromophore by Using a Totally Unconstrained Theoretical Approach. J Chem Theory Comput 2011; 7:4088-96. [DOI: 10.1021/ct200646r] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Angelo Giussani
- Instituto de Ciencia Molecular, Universitat de València, Apartado 22085, ES-46071 Valencia, Spain
| | - Manuela Merchán
- Instituto de Ciencia Molecular, Universitat de València, Apartado 22085, ES-46071 Valencia, Spain
| | - Daniel Roca-Sanjuán
- Department of Chemistry − Ångstrom, Theoretical Chemistry Program, Uppsala University Box 518, 75120 Uppsala, Sweden
| | - Roland Lindh
- Department of Chemistry − Ångstrom, Theoretical Chemistry Program, Uppsala University Box 518, 75120 Uppsala, Sweden
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