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Kossoski F, Boggio-Pasqua M, Loos PF, Jacquemin D. Reference Energies for Double Excitations: Improvement and Extension. J Chem Theory Comput 2024; 20:5655-5678. [PMID: 38885174 DOI: 10.1021/acs.jctc.4c00410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
In the realm of photochemistry, the significance of double excitations (also known as doubly excited states), where two electrons are concurrently elevated to higher energy levels, lies in their involvement in key electronic transitions essential in light-induced chemical reactions as well as their challenging nature from the computational theoretical chemistry point of view. Based on state-of-the-art electronic structure methods (such as high-order coupled-cluster, selected configuration interaction, and multiconfigurational methods), we improve and expand our prior set of accurate reference excitation energies for electronic states exhibiting a substantial amount of double excitations [Loos et al. J. Chem. Theory Comput. 2019, 15, 1939]. This extended collection encompasses 47 electronic transitions across 26 molecular systems that we separate into two distinct subsets: (i) 28 "genuine" doubly excited states where the transitions almost exclusively involve doubly excited configurations and (ii) 19 "partial" doubly excited states which exhibit a more balanced character between singly and doubly excited configurations. For each subset, we assess the performance of high-order coupled-cluster (CC3, CCSDT, CC4, and CCSDTQ) and multiconfigurational methods (CASPT2, CASPT3, PC-NEVPT2, and SC-NEVPT2). Using as a probe the percentage of single excitations involved in a given transition (%T1) computed at the CC3 level, we also propose a simple correction that reduces the errors of CC3 by a factor of 3, for both sets of excitations. We hope that this more complete and diverse compilation of double excitations will help future developments of electronic excited-state methodologies.
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Affiliation(s)
- Fábris Kossoski
- Laboratoire de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Martial Boggio-Pasqua
- Laboratoire de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Pierre-François Loos
- Laboratoire de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Denis Jacquemin
- Nantes Université, CNRS, CEISAM UMR 6230, F-44000 Nantes, France
- Institut Universitaire de France (IUF), F-75005 Paris, France
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2
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Masthay MB, McLean JB, Santos AL, Pirlo RK, Biffinger JC. Calculation of the Relative Basicity of Three α,ω‐Diphenylpolyenes with Trifluoroacetic Acid. J PHYS ORG CHEM 2022. [DOI: 10.1002/poc.4412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Mark B. Masthay
- Chemistry Department, University of Dayton 300 College Park Dayton OH U.S.A
| | - Jack B. McLean
- Chemistry Department, University of Dayton 300 College Park Dayton OH U.S.A
| | - Ariana L. Santos
- Chemistry Department, University of Dayton 300 College Park Dayton OH U.S.A
| | - Russell K. Pirlo
- Chemical Engineering Department, University of Dayton 300 College Park Dayton OH
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Manna S, Chaudhuri RK, Chattopadhyay S. Taming the excited states of butadiene, hexatriene, and octatetraene using state specific multireference perturbation theory with density functional theory orbitals. J Chem Phys 2020; 152:244105. [DOI: 10.1063/5.0007198] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Shovan Manna
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103, India
| | | | - Sudip Chattopadhyay
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103, India
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Loos PF, Boggio-Pasqua M, Scemama A, Caffarel M, Jacquemin D. Reference Energies for Double Excitations. J Chem Theory Comput 2019; 15:1939-1956. [DOI: 10.1021/acs.jctc.8b01205] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Pierre-François Loos
- Laboratoire de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Martial Boggio-Pasqua
- Laboratoire de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Anthony Scemama
- Laboratoire de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Michel Caffarel
- Laboratoire de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Denis Jacquemin
- Laboratoire CEISAM (UMR 6230), CNRS, Université de Nantes, 44399 Cedex 3 Nantes, France
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Mewes SA, Plasser F, Krylov A, Dreuw A. Benchmarking Excited-State Calculations Using Exciton Properties. J Chem Theory Comput 2018; 14:710-725. [DOI: 10.1021/acs.jctc.7b01145] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Stefanie A. Mewes
- Interdisciplinary
Center for Scientific Computing, Ruprecht-Karls University, Im Neuenheimer Feld 205A, D-69120 Heidelberg, Germany
- Centre
for Theoretical Chemistry and Physics, The New Zealand Institute for
Advanced Study (NZIAS), Massey University Albany, Private Bag 102904, Auckland 0745, New Zealand
| | - Felix Plasser
- Institute
for Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währingstrasse 17, A-1090 Wien, Austria
| | - Anna Krylov
- University of Southern California Los Angeles, Los Angeles, California 90089-0482, United States
| | - Andreas Dreuw
- Interdisciplinary
Center for Scientific Computing, Ruprecht-Karls University, Im Neuenheimer Feld 205A, D-69120 Heidelberg, Germany
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6
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Lyskov I, Köppel H, Marian CM. Nonadiabatic photodynamics and UV absorption spectrum of all-trans-octatetraene. Phys Chem Chem Phys 2017; 19:3937-3947. [PMID: 28106190 DOI: 10.1039/c6cp07640h] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The short-time molecular quantum dynamics of all-trans-octatetraene after electronic excitation to the first bright valence state is theoretically investigated.
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Affiliation(s)
- Igor Lyskov
- Institute of Theoretical and Computational Chemistry
- Heinrich-Heine-University Düsseldorf
- 40225 Düsseldorf
- Germany
| | - Horst Köppel
- Physikalisch-Chemisches Institut
- Universität Heidelberg
- D-69120 Heidelberg
- Germany
| | - Christel M. Marian
- Institute of Theoretical and Computational Chemistry
- Heinrich-Heine-University Düsseldorf
- 40225 Düsseldorf
- Germany
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7
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Firmansyah D, Deperasińska I, Vakuliuk O, Banasiewicz M, Tasior M, Makarewicz A, Cyrański MK, Kozankiewicz B, Gryko DT. Double head-to-tail direct arylation as a viable strategy towards the synthesis of the aza-analog of dihydrocyclopenta[hi]aceanthrylene – an intriguing antiaromatic heterocycle. Chem Commun (Camb) 2016; 52:1262-5. [DOI: 10.1039/c5cc08716c] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Straightforwardly prepared head-to-tail bis-imidazo[1,2-a]pyridine displays antiaromaticity and no fluorescence.
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Affiliation(s)
| | | | - Olena Vakuliuk
- Institute of Organic Chemistry
- Polish Academy of Sciences
- 01-224 Warsaw
- Poland
| | | | - Mariusz Tasior
- Institute of Organic Chemistry
- Polish Academy of Sciences
- 01-224 Warsaw
- Poland
| | - Artur Makarewicz
- Institute of Physics
- Polish Academy of Sciences
- 02-668 Warsaw
- Poland
| | | | | | - Daniel T. Gryko
- Warsaw University of Technology
- 00-664 Warsaw
- Poland
- Institute of Organic Chemistry
- Polish Academy of Sciences
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8
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Renth F, Siewertsen R, Strübe F, Mattay J, Temps F. Ultrafast Z → E photoisomerisation of structurally modified furylfulgides. Phys Chem Chem Phys 2014; 16:19556-63. [DOI: 10.1039/c4cp01739k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Femtosecond transient absorption spectroscopy of Z-fulgides with selected structural motifs revealed fast and direct excited-state dynamics independent of chemical modifications.
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Affiliation(s)
- Falk Renth
- Institut für Physikalische Chemie
- Christian-Albrechts-Universität zu Kiel
- D-24098 Kiel, Germany
| | - Ron Siewertsen
- Institut für Physikalische Chemie
- Christian-Albrechts-Universität zu Kiel
- D-24098 Kiel, Germany
| | - Frank Strübe
- Organische Chemie I
- Fakultät für Chemie
- Universität Bielefeld
- D-33501 Bielefeld, Germany
| | - Jochen Mattay
- Organische Chemie I
- Fakultät für Chemie
- Universität Bielefeld
- D-33501 Bielefeld, Germany
| | - Friedrich Temps
- Institut für Physikalische Chemie
- Christian-Albrechts-Universität zu Kiel
- D-24098 Kiel, Germany
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Qu Z, Liu C. A non-adiabatic dynamics study of octatetraene: The radiationless conversion from S2 to S1. J Chem Phys 2013; 139:244304. [PMID: 24387367 DOI: 10.1063/1.4853715] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Zexing Qu
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry of the Ministry of Education (MOE), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Chungen Liu
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry of the Ministry of Education (MOE), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
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Kirkus M, Knippenberg S, Beljonne D, Cornil J, Janssen RAJ, Meskers SCJ. Synthesis and Optical Properties of Pyrrolo[3,2-b]pyrrole-2,5(1H,4H)-dione (iDPP)-Based Molecules. J Phys Chem A 2013; 117:2782-9. [DOI: 10.1021/jp400256s] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Mindaugas Kirkus
- Molecular Materials and Nanosystems, Eindhoven University of Technology, P.O. Box 513, 5600
MB Eindhoven, The Netherlands
| | - Stefan Knippenberg
- Laboratory for Chemistry of
Novel Materials, University of Mons, Place
du Parc 20, B-7000 Mons, Belgium
| | - David Beljonne
- Laboratory for Chemistry of
Novel Materials, University of Mons, Place
du Parc 20, B-7000 Mons, Belgium
| | - Jérôme Cornil
- Laboratory for Chemistry of
Novel Materials, University of Mons, Place
du Parc 20, B-7000 Mons, Belgium
| | - René A. J. Janssen
- Molecular Materials and Nanosystems, Eindhoven University of Technology, P.O. Box 513, 5600
MB Eindhoven, The Netherlands
| | - Stefan C. J. Meskers
- Molecular Materials and Nanosystems, Eindhoven University of Technology, P.O. Box 513, 5600
MB Eindhoven, The Netherlands
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11
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Renth F, Siewertsen R, Temps F. Enhanced photoswitching and ultrafast dynamics in structurally modified photochromic fulgides. INT REV PHYS CHEM 2013. [DOI: 10.1080/0144235x.2012.729331] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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12
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Petrenko T, Neese F. Efficient and automatic calculation of optical band shapes and resonance Raman spectra for larger molecules within the independent mode displaced harmonic oscillator model. J Chem Phys 2012; 137:234107. [DOI: 10.1063/1.4771959] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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13
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Assessment of dressed time-dependent density-functional theory for the low-lying valence states of 28 organic chromophores. Chem Phys 2011. [DOI: 10.1016/j.chemphys.2011.03.019] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Angeli C, Pastore M. The lowest singlet states of octatetraene revisited. J Chem Phys 2011; 134:184302. [DOI: 10.1063/1.3585607] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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15
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Deperasińska I, Szemik-Hojniak A, Osowska K, Rode M, Szczepanik A, Wiśniewski Ł, Lis T, Szafert S. Synthesis, photophysics and excited state structure of 1,8-di(p-tolyl)-1,3,5,7-octatetrayne. J Photochem Photobiol A Chem 2011. [DOI: 10.1016/j.jphotochem.2010.10.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Mazur G, Włodarczyk R. Application of the dressed time-dependent density functional theory for the excited states of linear polyenes. J Comput Chem 2009; 30:811-7. [PMID: 18727156 DOI: 10.1002/jcc.21102] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Dressed Time-Dependent Density Functional Theory (Maitra et al., J Chem Phys 2004, 120, 5932) is applied to selected linear polyenes. Limits of validity of the approximation are briefly discussed. The implementation strategy is described. Results for the 2(1)B(u) and 2(1)A(g) states of selected linear polyenes are presented and compared with accessible experimental and theoretical results.
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Affiliation(s)
- Grzegorz Mazur
- Department of Computational Methods in Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland.
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17
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Detert H, Lenoir D, Zipse H. Thermal Rearrangements of Perchlorohexatrienes-Structures and Experimental and Theoretical Evaluation of Pathways to Isomerization and Cyclization. European J Org Chem 2009. [DOI: 10.1002/ejoc.200801076] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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18
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Marian CM, Gilka N. Performance of the Density Functional Theory/Multireference Configuration Interaction Method on Electronic Excitation of Extended π-Systems. J Chem Theory Comput 2008; 4:1501-15. [DOI: 10.1021/ct8001738] [Citation(s) in RCA: 151] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christel M. Marian
- Institute of Theoretical and Computational Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstraβe 1, 40225 Düsseldorf, Germany
| | - Natalie Gilka
- Institute of Theoretical and Computational Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstraβe 1, 40225 Düsseldorf, Germany
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Catalán J, Pérez P, Hopf H, Klein D. The photophysics of all-trans polyenes from ttbP5, a nonphotolabile pentaene. J Chem Phys 2008; 129:014505. [DOI: 10.1063/1.2952270] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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20
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Catalán J, Hopf H, Martus M. New contributions to the photophysical model for all-trans-polyenesfrom ttbP4, a nonphotolabile octatetraene. J Chem Phys 2008; 128:104504. [DOI: 10.1063/1.2839590] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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21
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Petrenko T, Neese F. Analysis and prediction of absorption band shapes, fluorescence band shapes, resonance Raman intensities, and excitation profiles using the time-dependent theory of electronic spectroscopy. J Chem Phys 2008; 127:164319. [PMID: 17979350 DOI: 10.1063/1.2770706] [Citation(s) in RCA: 211] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A general method for the simulation of absorption (ABS) and fluorescence band shapes, resonance-Raman (rR) spectra, and excitation profiles based on the time-dependent theory of Heller is discussed. The following improvements to Heller's theory have been made: (a) derivation of new recurrence relations for the time-dependent wave packet overlap in the case of frequency changes between the ground and electronically excited states, (b) a new series expansion that gives insight into the nature of Savin's preresonance approximation, (c) incorporation of inhomogeneous broadening effects into the formalism at no additional computational cost, and (d) derivation of a new and simple short-time dynamics based equation for the Stokes shift that remains valid in the case of partially resolved vibrational structure. Our implementation of the time-dependent theory for the fitting of experimental spectra and the simulation of model spectra as well as the quantum mechanical calculation of the model parameters is discussed. The implementation covers all electronic structure approaches which are able to deliver ground- and excited-state energies and transition dipole moments. The technique becomes highly efficient if analytic gradients for the excited-state surface are available. In this case, the computational cost for the simultaneous prediction of ABS, fluorescence, and rR spectra is equal to that of a single excited-state geometry optimization step while the limitations of the short-time dynamics approximation are completely avoided. As a test case we discuss the well-known case of the strongly allowed 1 (1)A(g) --> 1 (1)B(u) transition in 1,3,5 trans-hexatriene in detail using method ranging from simple single-reference treatments to elaborate multireference electronic structure approaches. At the highest computational level, the computed spectra show the best agreement that has so far been obtained with quantum chemical methods for this problem.
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Affiliation(s)
- Taras Petrenko
- Lehrstuhl für Theoretische Chemie, Universität Bonn, Wegelerstrasse 12, 53115 Bonn, Germany
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Barbatti M, Ruckenbauer M, Szymczak JJ, Aquino AJA, Lischka H. Nonadiabatic excited-state dynamics of polar π-systems and related model compounds of biological relevance. Phys Chem Chem Phys 2008; 10:482-94. [DOI: 10.1039/b709315m] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Deperasińska I, Zehnacker A, Lahmani F, Borowicz P, Sepioł J. Fluorescence Studies of Terrylene in a Supersonic Jet: Indication of A Dark Electronic State Below the Allowed Transition. J Phys Chem A 2007; 111:4252-8. [PMID: 17447744 DOI: 10.1021/jp070337o] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Jet-cooled terrylene has been studied in helium buffer gas using a pulsed nozzle by means of laser-induced fluorescence. Fluorescence excitation and two-color depletion experiments (resulting in hole burning spectra) are presented. Analysis of the spectra leads to the conclusion that another excited electronic state is present in the vicinity of the allowed 1B1u state. Assuming (according to previous literature suggestions Karabunarliev, S.; Baumgarten, M.; Müllen, K. J. Phys. Chem. A 1998, 102, 7029) that this dark state is the 21Ag state, we discuss the vibrational structure of the fluorescence excitation spectrum in terms of two manifolds of vibronic states belonging to Sd(21Ag) and S1(1B1u) states. The anomalous shift between excitation and dispersed fluorescence spectra observed earlier for terrylene in a neon matrix is discussed as a consequence of terrylene electronic relaxation to the low-energy dark state.
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Affiliation(s)
- I Deperasińska
- Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland.
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Gurzadyan GG, Reynisson J, Steenken S. Photoionization versus photoheterolysis of all-trans-retinol. The effects of solvent and laser radiation intensity. Phys Chem Chem Phys 2006; 9:288-98. [PMID: 17186072 DOI: 10.1039/b609165m] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The time-resolved formation of the retinyl carbocation from all-trans-retinol and all-trans-retinol acetate was studied by use of picosecond flash photolysis. From both precursors, the retinyl cation is produced by heterolytic C-O bond cleavage in solvents of medium polarity (acetonitrile, tetrahydrofuran, propanol with Reichardt polarity parameter ET(N) approximately 0.5) and high polarity (EtOH, MeOH, TFE, HFIP, ET(N) > 0.6) during the laser pulse (< or =5 ps) where its lifetime is >10 ns. The absorption maximum of the cation at early times (t < 100 ps) is at lambda = 590-600 nm; it shifts to shorter wavelengths (Deltalambda = 5-10 nm) within 1-10 ns. This spectral shift is suggested to be due to contact ion pair --> solvent-separated ion pair --> free-ion transformation. The quantum yield of cation formation phi(cat) is independent of excitation wavelength (213, 266 or 355 nm). Photoheterolysis proceeds via a one-quantum process. In chlorinated solvents, i.e. n-BuCl, 1,2-dichloroethane, chloroform or CCl(4), formation of the retinol radical cation (which is characterized by a peak at 610 nm and further absorption maxima at approximately 840 and approximately 940 nm) by intermolecular electron transfer to the solvent molecules was detected. The radical cation lifetime in all these solvents is 1.5-2 ns, except for CCl(4) where it is 0.25 ns. The formation of the radical cation or cation was not detected in the low polarity solvents: cyclohexane, hexane, dioxane and p-xylene. However, in solvents of medium and high polarity, at high radiation intensities the radical cation may form in addition to the cation (as a result of two-quantum ionization). DFT calculations confirm our experimental results. The rate of retinol S(1) depopulation (k = 0.3-1 x 10(9) s(-1)) is almost independent of the solvent polarity in the range from cyclohexane to methanol. In highly polar solvents (ET(N) > 0.9) the rate increases to (0.5-5) x 10(10) s(-1).
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Affiliation(s)
- Gagik G Gurzadyan
- Max-Planck-Institut für Bioanorganische Chemie (formerly Max-Planck-Institut für Strahlenchemie), D-45413, Mülheim, Germany.
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