1
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Kochman MA. Nonadiabatic Molecular Dynamics Simulations Provide Evidence for Coexistence of Planar and Nonplanar Intramolecular Charge Transfer Structures in Fluorazene. J Phys Chem A 2024; 128:6685-6694. [PMID: 39109856 PMCID: PMC11331525 DOI: 10.1021/acs.jpca.4c03693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2024] [Revised: 07/18/2024] [Accepted: 07/22/2024] [Indexed: 08/16/2024]
Abstract
Fluorazene is a model compound for photoinduced intramolecular charge transfer (ICT) between aromatic moieties. Despite intensive studies, both spectroscopic and theoretical, a complete model of its photophysics is still lacking. Especially controversial is the geometry of its ICT structure, or structures. In order to fill in the gaps in the state of knowledge on this important model system, in the present study I report the results of nonadiabatic molecular dynamics (NAMD) simulations of its photorelaxation process in acetonitrile solution. To afford a direct comparison to spectroscopic data, I use the simulation results as the basis for the calculation of the transient absorption (TA) spectrum. The NAMD simulations provide detailed information on the sequence of events during the excited-state relaxation of the title compound. Following initial photoexcitation into the bright S2 state, the molecule undergoes rapid internal conversion into the S1 state, leading to the locally excited (LE) structure. The LE structure, in turn, undergoes isomerization into a population of ICT structures, with geometries ranging from near-planar to markedly nonplanar. The LE → ICT isomerization reaction is accompanied by the decay of the characteristic excited-state absorption band of the LE structure near 2 eV. The anomalous fluorescence emission band of fluorazene is found to originate mainly from the near-planar ICT structures, in part because they dominate the overall population of ICT structures. Thus, the planar ICT (PICT) model appears to be the most appropriate description of the geometry of the ICT structure of fluorazene.
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Affiliation(s)
- Michał Andrzej Kochman
- Institute
of Physical Chemistry of the Polish Academy of Sciences, Ul. Marcina Kasprzaka 44/52, 01-224 Warsaw, Poland
- Theoretical
Chemistry, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
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2
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Abelt C, Day I, Zhao J, Pike R. Fluorescence of Half-Twisted 10-Acyl-1-methyltetrahydrobenzoquinolines. Molecules 2024; 29:3016. [PMID: 38998968 PMCID: PMC11243386 DOI: 10.3390/molecules29133016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 06/18/2024] [Accepted: 06/20/2024] [Indexed: 07/14/2024] Open
Abstract
The steric interference of proximal dialkyl amino and acyl groups at the peri (1,8) positions of naphthalene affects the intramolecular charge transfer fluorescence. Previous studies indicate that acyl and freely rotating dimethyl amino groups twist toward coplanarity with the naphthalene ring in the excited state. The present study examines the effect of constraining the amino group in a ring. The photophysical properties of 2,2-dimethyl-1-(1-methyl-1,2,3,4-tetrahydrobenzo[h]quinolin-10-yl)propan-1-one (4), ethyl 1-methyl-1,2,3,4-tetrahydrobenzo[h]quinoline-10-carboxylate (5), and 1-methyl-1,2,3,4-tetrahydrobenzo[h]quinoline-10-carbaldehyde (6) are compared with the dimethyl amino derivatives 2 and 3. Crystal structures of 4-6 show that the amine ring adopts a chair conformation, where the N-methyl group is axial. Computational results suggest that the pyramidal amino group planarizes and twists together with the acyl toward coplanarity in the excited state. The ring structure does not thwart the formation of a planar intramolecular charge transfer (PICT) state.
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Affiliation(s)
- Christopher Abelt
- Department of Chemistry, College of William and Mary, Williamsburg, VA 23185, USA; (I.D.); (J.Z.); (R.P.)
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3
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Charette BJ, King SR, Chen J, Holm AR, Malme JT, Cook RD, Schaller RD, Jackson NE, Olshansky L. Excited State Dynamics of a Conformationally Fluxional Copper Coordination Complex. J Phys Chem A 2023; 127:7747-7755. [PMID: 37672011 DOI: 10.1021/acs.jpca.3c04269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
The conversion of solar energy into chemical fuel represents a capstone goal of the 21st century and has the potential to supply terawatts of power in a globally distributed manner. However, the disparate time scales of photodriven charge separation (∼fs) and steps in chemical reactions (∼μs) represent an inherent bottleneck in solar-to-fuels technology. To address this discrepancy, we are developing earth-abundant coordination complexes that undergo light-induced conformational rearrangements such that charge separation (CS) is hastened, while charge recombination (CR) is slowed. To these ends, we report the preparation and characterization of a new series of conformationally fluxional copper coordination complexes that contain a twisted intramolecular charge transfer (TICT) fluorophore as part of their ligand scaffold. Structural and spectroscopic characterization of the Cu(I) and Cu(II) complexes formed with these ligands in their ground states establish oxidation state-dependent conformational dynamicity, while time-resolved emission and transient absorption spectroscopies define the photophysical parameters of photo-induced excited states. Building on initial reports with a related set of molecules, the improved ligand design presented here greatly simplifies the observed photophysics, effectively shutting down unwanted ligand-centered excited states previously observed. Time-dependent density functional theory (TDDFT) analyses reveal an unusual metal-to-TICT electronic transition only reported once before, and though the formation of a CS state is not observed directly through experiments, TDDFT geometry optimizations in the excited states support the formation of transient Cu(II) CS species, lending credence to the potential success of our approach. These studies establish a clear model for the excited state dynamics at play in proof-of-concept systems and clarify key design parameters for future optimizations toward achieving long-lived CS via photoinduced conformational gating.
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Affiliation(s)
- Bronte J Charette
- University of Illinois, Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Shelby R King
- University of Illinois, Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Jiaqi Chen
- University of Illinois, Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Annika R Holm
- University of Illinois, Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Justin T Malme
- University of Illinois, Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Robert D Cook
- University of Illinois, Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Richard D Schaller
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Nicholas E Jackson
- University of Illinois, Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Lisa Olshansky
- University of Illinois, Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
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4
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Kochman MA, Durbeej B, Kubas A. Simulation and Analysis of the Transient Absorption Spectrum of 4-( N, N-Dimethylamino)benzonitrile (DMABN) in Acetonitrile. J Phys Chem A 2021; 125:8635-8648. [PMID: 34550700 PMCID: PMC8503879 DOI: 10.1021/acs.jpca.1c06166] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 09/03/2021] [Indexed: 12/17/2022]
Abstract
4-(N,N-Dimethylamino)benzonitrile (DMABN) is a well-known model compound for dual fluorescence-in sufficiently polar solvents, it exhibits two distinct fluorescence emission bands. The interpretation of its transient absorption (TA) spectrum in the visible range is the subject of a long-standing controversy. In the present study, we resolve this issue by calculating the TA spectrum on the basis of nonadiabatic molecular dynamics simulations. An unambiguous assignment of spectral signals to specific excited-state structures is achieved by breaking down the calculated spectrum into contributions from twisted and nontwisted molecular geometries. In particular, the much-discussed excited-state absorption band near 1.7 eV (ca. 700 nm) is attributed to the near-planar locally excited (LE) minimum on the S1 state. On the technical side, our study demonstrates that the second-order approximate coupled cluster singles and doubles (CC2) method can be used successfully to calculate the TA spectra of moderately large organic molecules, provided that the system in question does not approach a crossing between the lowest excited state and the singlet ground state within the time frame of the simulation.
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Affiliation(s)
- Michał Andrzej Kochman
- Institute
of Physical Chemistry, Polish Academy of
Sciences, Ul. Marcina Kasprzaka 44/52, 01-224 Warszawa, Poland
| | - Bo Durbeej
- Division
of Theoretical Chemistry, Department of Physics, Chemistry and Biology
(IFM), Linköping University, 581 83 Linköping, Sweden
| | - Adam Kubas
- Institute
of Physical Chemistry, Polish Academy of
Sciences, Ul. Marcina Kasprzaka 44/52, 01-224 Warszawa, Poland
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5
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The suppression of intramolecular charge transfer emission by tautomerism in 2-(4′-amino-2′-hydroxyphenyl)-1H-imidazo-[4,5-c]pyridine: Intramolecular proton transfer versus intermolecular proton transfer. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2021.113199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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6
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Abstract
Two derivatives of dansyl (1-dimethylamino-5-naphthalenesulfonyl) in which the amino group is constrained in a ring are prepared as neopentyl esters. Their photophysical behavior is compared with that of the dansyl ester. The solvatochromism and quantum yields are similar for all three. Since the two constrained derivatives cannot twist about the amino group, they must emit from a planar intramolecular charge-transfer excited state. The similar photophysical behavior suggests that dansyl also emits from a PICT excited state instead of a twisted intramolecular charge transfer state.
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Affiliation(s)
- Kristen Lum
- Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23185, United States
| | - Stephanie M Zielinski
- Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23185, United States
| | - Christopher J Abelt
- Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23185, United States
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7
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Kochman MA, Durbeej B. Simulating the Nonadiabatic Relaxation Dynamics of 4-( N, N-Dimethylamino)benzonitrile (DMABN) in Polar Solution. J Phys Chem A 2020; 124:2193-2206. [PMID: 32083861 DOI: 10.1021/acs.jpca.9b10588] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The compound 4-(N,N-dimethylamino)benzonitrile (DMABN) represents the archetypal system for dual fluorescence, a rare photophysical phenomenon in which a given fluorophore shows two distinct emission bands. Despite extensive studies, the underlying mechanism remains the subject of debate. In the present contribution, we address this issue by simulating the excited-state relaxation process of DMABN as it occurs in polar solution. The potential energy surfaces for the system are constructed with the use of the additive quantum mechanics/molecular mechanics (QM/MM) method, and the coupled dynamics of the electronic wave function and the nuclei is propagated with the semiclassical fewest switches surface hopping method. The DMABN molecule, which comprises the QM subsystem, is treated with the use of the second-order algebraic diagrammatic construction (ADC(2)) method with the imposition of spin-opposite scaling (SOS). It is verified that this level of theory achieves a realistic description of the excited-state potential energy surfaces of DMABN. The simulation results qualitatively reproduce the main features of the experimentally observed fluorescence spectrum, thus allowing the unambiguous assignment of the two fluorescence bands: the normal band is due to the near-planar locally excited (LE) structure of DMABN, while the so-called "anomalous" second band arises from the twisted intramolecular charge transfer (TICT) structure. The transformation of the LE structure into the TICT structure takes place directly via intramolecular rotation, and is not mediated by another excited-state structure. In particular, the oft-discussed rehybridized intramolecular charge transfer (RICT) structure, which is characterized by a bent nitrile group, does not play a role in the relaxation process.
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Affiliation(s)
- Michał Andrzej Kochman
- Division of Theoretical Chemistry, Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83 Linköping, Sweden.,Department of Chemistry, University College London (UCL), 20 Gordon Street, London WC1H 0A, United Kingdom
| | - Bo Durbeej
- Division of Theoretical Chemistry, Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83 Linköping, Sweden
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8
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Zachariasse KA, Druzhinin SI, Morawski O, Kozankiewicz B. Fluorescence of 4-(Diisopropylamino)benzonitrile (DIABN) Single Crystals from 300 K down to 5 K. Intramolecular Charge Transfer Disappears below 60 K. J Phys Chem A 2018; 122:6985-6996. [DOI: 10.1021/acs.jpca.8b06349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Klaas A. Zachariasse
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany
| | - Sergey I. Druzhinin
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany
| | - Olaf Morawski
- Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Boleslaw Kozankiewicz
- Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
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9
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Suda K, Yokogawa D. Theoretical Study on Nonradiative Decay of Dimethylaminobenzonitrile through Triplet State in Gas-Phase, Nonpolar, and Polar Solutions. J Phys Chem B 2017; 121:2164-2170. [DOI: 10.1021/acs.jpcb.6b11654] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Kayo Suda
- Department
of Chemistry, Graduate School of Science and ‡Institute of Transformative Bio-Molecules
(WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8602, Japan
| | - Daisuke Yokogawa
- Department
of Chemistry, Graduate School of Science and ‡Institute of Transformative Bio-Molecules
(WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8602, Japan
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10
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Aloïse S, Pawlowska Z, Ruckebusch C, Sliwa M, Dubois J, Poizat O, Buntinx G, Perrier A, Maurel F, Jacques P, Malval JP, Poisson L, Piani G, Abe J. A two-step ICT process for solvatochromic betaine pyridinium revealed by ultrafast spectroscopy, multivariate curve resolution, and TDDFT calculations. Phys Chem Chem Phys 2012; 14:1945-56. [DOI: 10.1039/c2cp22254j] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Wink C, Schollmeyer D, Detert H. 4-Diethyl-amino-3,5-diisopropyl-benzalde-hyde. Acta Crystallogr Sect E Struct Rep Online 2011; 67:o3336. [PMID: 22199832 PMCID: PMC3238983 DOI: 10.1107/s1600536811047672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 11/10/2011] [Indexed: 05/31/2023]
Abstract
The title benzaldehyde, C(17)H(27)NO, was prepared via lithia-tion of bromoaniline and reaction with DMF. In the crystal, the molecule adopts a C2-symmetrical conformation; nevertheless, two modes of disorder are present: the orientation of the aldehyde group (occupancy ratio 0.5:0.5) and of symmetry-equivalent ethyl groups [occupancy ratio 0.595 (7):0.405 (7)]. The phenyl-ene ring and the carbonyl group are essentially coplanar [C-C-C-O torsion angle = -179.0 (4)°] but the dihedral angle between the mean planes of the phenyl-ene ring and the amino group = 67.5 (2)°. This and the long [1.414 (3) Å] aniline C-N bond indicate electronic decoupling between the carbonyl and amino groups. The angle sum of 359.9 (2)° around the N atom results from steric compression-induced rehybridization.
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Affiliation(s)
- Christoph Wink
- University Mainz, Duesbergweg 10-14, 55099 Mainz, Germany
| | | | - Heiner Detert
- University Mainz, Duesbergweg 10-14, 55099 Mainz, Germany
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12
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Coto PB, Serrano-Andrés L, Gustavsson T, Fujiwara T, Lim EC. Intramolecular charge transfer and dual fluorescence of 4-(dimethylamino)benzonitrile: ultrafast branching followed by a two-fold decay mechanism. Phys Chem Chem Phys 2011; 13:15182-8. [PMID: 21769358 DOI: 10.1039/c1cp21089k] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this contribution we present new experimental and theoretical results for the intramolecular charge transfer (ICT) reaction underlying the dual fluorescence of 4-(dimethylamino)benzonitrile (DMABN), which indicate that the fully twisted ICT (TICT) state is responsible for the time-resolved transient absorption spectrum while a distinct partially twisted ICT (pTICT) structure is suggested for the fluorescent ICT state.
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Affiliation(s)
- Pedro B Coto
- Interdisziplinäres Zentrum für Molekulare Materialien (ICMM), Friedrich-Alexander-Universität Erlangen-Nürnberg Staudtstrasse 7/B2, D-91058 Erlangen, Germany.
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13
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Everett RK, Nguyen HAA, Abelt CJ. Does PRODAN possess an O-TICT excited state? Synthesis and properties of two constrained derivatives. J Phys Chem A 2010; 114:4946-50. [PMID: 20329761 DOI: 10.1021/jp1002808] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis and photophysical properties of 7-(dimethylamino)-3,4-dihydrophenanthren-1(2H)-one (7) and 3-(dimethylamino)-8,9,10,11-tetrahydro-7H-cyclohepta[a]naphthalen-7-one (8) are reported. These compounds possess a cycloalkanone substructure that controls the extent of twisting of the carbonyl group. The six-membered ring in 7 forces the carbonyl group to be coplanar with the naphthalene ring, whereas the seven-membered ring in 8 induces a significant twist. Both have the substructure of PRODAN (6-propionyl-2-(dimethylamino)naphthalene, 1). Comparing the photophysical behavior of these compounds with that of PRODAN and 2,2-dimethyl-1-(4-methyl-1,2,3,4-tetrahydrobenzo[f]quinolin-8-yl)propan-1-one (3) indicates that PRODAN likely emits from a PICT excited state rather than from an O-TICT excited state.
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Affiliation(s)
- Renata K Everett
- Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795, USA
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14
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Rhinehart JM, Mehlenbacher RD, McCamant D. Probing the Charge Transfer Reaction Coordinate of 4-(Dimethylamino)benzonitrile with Femtosecond Stimulated Raman Spectroscopy. J Phys Chem B 2010; 114:14646-56. [DOI: 10.1021/jp1023982] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Justin M. Rhinehart
- Department of Chemistry, University of Rochester, Rochester, New York 14627-0216
| | | | - David McCamant
- Department of Chemistry, University of Rochester, Rochester, New York 14627-0216
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15
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Zgierski MZ, Fujiwara T, Lim EC. Role of the pisigma* state in molecular photophysics. Acc Chem Res 2010; 43:506-17. [PMID: 20078111 DOI: 10.1021/ar9002043] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Photosynthesis, which depends on light-driven energy and electron transfer in assemblies of porphyrins, chlorophylls, and carotenoids, is just one example of the many complex natural systems of photobiology. A fuller understanding of the spectroscopy and photophysics of simple aromatic molecules is central to elucidating photochemical processes in the more sophisticated assemblies of photobiology. Moreover, developing a better grasp of the photophysics of simple aromatic molecules will also enhance our ability to create and improve practical applications in photochemical energy conversion, molecular nanophotonics, and molecular electronics. In this Account, we present a concerted experimental and theoretical study of aromatic ethynes, aromatic nitriles, and fluorinated benzenes, illustrating the important roles that the low-lying pisigma* state plays in the electronic relaxation of these aromatic compounds. Diphenylacetylene, 4-dialkylaminobenzonitriles, 4-dialkylaminobenzethynes, and fluorinated benzenes exhibit fluorescence that strongly quenches as the excitation energy is increased for gas-phase systems and at elevated temperatures in solution. Much of this interesting photophysical behavior can be attributed to the presence of a dark intermediate state that crosses the fluorescent pipi* state. Our quantum chemistry calculations, as well as time-resolved laser spectroscopies, indicate that this dark intermediate state is the pisigma* state that arises from the promotion of an electron from the pi orbital of the phenyl ring to the sigma* orbital localized in the C[triple bond]X group (where X is CH and N) or on the C-X group (where X is a halogen). These crossings not only lead to the strong excitation energy and temperature dependence of fluorescence but also induce highly interesting pisigma*-mediated intramolecular charge transfer in 4-dialkylaminobenzonitriles. Most previous studies on the excited-state dynamics of organic molecules have examined aromatic hydrocarbons, nitrogen heterocycles, aromatic carbonyl compounds, and polyenes, which have low-lying excited states of pipi* character (hydrocarbons and polyenes) or npi* and pipi* character (carbonyls and N-heterocycles). These studies have revealed important involvement of selection rules (promoting vibrational modes and spin-orbit coupling) and Franck-Condon factors for radiationless transitions, which have important effects on photophysical properties. The recent experimental and time-dependent density functional theory (TDDFT) calculations of aromatic ethynes, nitriles, and perfluorinated benzenes described in this Account demonstrate the importance of the bound excited state of a pisigma* configuration in these molecules.
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Affiliation(s)
- Marek Z. Zgierski
- Steacie Institute for Molecular Science, National Research Council of Canada, Ottawa K1A 0R6, Canada and
| | - Takashige Fujiwara
- Department of Chemistry and The Center for Laser and Optical Spectroscopy, The University of Akron, Akron, Ohio 44325-3601
| | - Edward C. Lim
- Department of Chemistry and The Center for Laser and Optical Spectroscopy, The University of Akron, Akron, Ohio 44325-3601
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16
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Zachariasse KA, Druzhinin SI, Kovalenko SA, Senyushkina T. Intramolecular charge transfer of 4-(dimethylamino)benzonitrile probed by time-resolved fluorescence and transient absorption: No evidence for two ICT states and a πσ∗ reaction intermediate. J Chem Phys 2009; 131:224313. [DOI: 10.1063/1.3270165] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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17
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Zachariasse KA, Druzhinin SI, Mayer P, Kovalenko SA, Senyushkina T. Decay times of 4-(dimethylamino)benzonitrile in acetonitrile and conclusions on entropy of activation. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.10.094] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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18
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Fujiwara T, Lee JK, Zgierski MZ, Lim EC. Intramolecular charge transfer in the excited state of 4-dimethylaminobenzaldehyde and 4-dimethylaminoacetophenone. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.09.053] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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19
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Gustavsson T, Coto PB, Serrano-Andrés L, Fujiwara T, Lim EC. Do fluorescence and transient absorption probe the same intramolecular charge transfer state of 4-(dimethylamino)benzonitrile? J Chem Phys 2009; 131:031101. [DOI: 10.1063/1.3173609] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Druzhinin SI, Kovalenko SA, Senyushkina TA, Demeter A, Machinek R, Noltemeyer M, Zachariasse KA. Intramolecular Charge Transfer with the Planarized 4-Cyanofluorazene and Its Flexible Counterpart 4-Cyano-N-phenylpyrrole. Picosecond Fluorescence Decays and Femtosecond Excited-State Absorption. J Phys Chem A 2008; 112:8238-53. [DOI: 10.1021/jp8037413] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sergey I. Druzhinin
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie and Photochemische Kinetik, 37070 Göttingen, Germany, Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor Strasse 2, 12489 Berlin, Germany, Institute of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences. P. O. Box 17, 1525 Budapest, Hungary, Institut für Organische Chemie, Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany, and Institut für Anorganische Chemie,
| | - Sergey A. Kovalenko
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie and Photochemische Kinetik, 37070 Göttingen, Germany, Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor Strasse 2, 12489 Berlin, Germany, Institute of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences. P. O. Box 17, 1525 Budapest, Hungary, Institut für Organische Chemie, Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany, and Institut für Anorganische Chemie,
| | - Tamara A. Senyushkina
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie and Photochemische Kinetik, 37070 Göttingen, Germany, Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor Strasse 2, 12489 Berlin, Germany, Institute of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences. P. O. Box 17, 1525 Budapest, Hungary, Institut für Organische Chemie, Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany, and Institut für Anorganische Chemie,
| | - Attila Demeter
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie and Photochemische Kinetik, 37070 Göttingen, Germany, Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor Strasse 2, 12489 Berlin, Germany, Institute of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences. P. O. Box 17, 1525 Budapest, Hungary, Institut für Organische Chemie, Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany, and Institut für Anorganische Chemie,
| | - Reinhard Machinek
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie and Photochemische Kinetik, 37070 Göttingen, Germany, Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor Strasse 2, 12489 Berlin, Germany, Institute of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences. P. O. Box 17, 1525 Budapest, Hungary, Institut für Organische Chemie, Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany, and Institut für Anorganische Chemie,
| | - Mathias Noltemeyer
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie and Photochemische Kinetik, 37070 Göttingen, Germany, Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor Strasse 2, 12489 Berlin, Germany, Institute of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences. P. O. Box 17, 1525 Budapest, Hungary, Institut für Organische Chemie, Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany, and Institut für Anorganische Chemie,
| | - Klaas A. Zachariasse
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie and Photochemische Kinetik, 37070 Göttingen, Germany, Institut für Chemie, Humboldt Universität zu Berlin, Brook-Taylor Strasse 2, 12489 Berlin, Germany, Institute of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences. P. O. Box 17, 1525 Budapest, Hungary, Institut für Organische Chemie, Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany, and Institut für Anorganische Chemie,
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Mondal JA, Ghosh HN, Ghanty TK, Mukherjee T, Palit DK. Twisting Dynamics in the Excited Singlet State of Michler's Ketone. J Phys Chem A 2006; 110:3432-46. [PMID: 16526622 DOI: 10.1021/jp0555450] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ultrafast relaxation dynamics of the excited singlet (S(1)) state of Michler's ketone (MK) has been investigated in different kinds of solvents using a time-resolved absorption spectroscopic technique with 120 fs time resolution. This technique reveals that conversion of the locally excited (LE) state to the twisted intramolecular charge transfer (TICT) state because of twisting of the N,N-dimethylanilino groups with respect to the central carbonyl group is the major relaxation process responsible for the multi-exponential and probe-wavelength-dependent transient absorption dynamics of the S1 state of MK, but solvation dynamics does not have a significant role in this process. Theoretical optimization of the ground-state geometry of MK shows that the dimethylanilino groups attached to the central carbonyl group are at a dihedral angle of about 51 degrees with respect to each other because of steric interaction between the phenyl rings. Following photoexcitation of MK to its S1 state, two kinds of twisting motions have been resolved. Immediately after photoexcitation, an ultrafast "anti-twisting" motion of the dimethylanilino groups brings back the pretwisted molecule to a near-planar geometry with high mesomeric interaction and intramolecular charge transfer (ICT) character. This motion is observed in all kinds of solvents. Additionally, in solvents of large polarity, the dimethylamino groups undergo further twisting to about 90 degrees with respect to the phenyl ring, to which it is attached, leading to the conversion of the ICT state to the TICT state. Similar characteristics of the absorption spectra of the TICT state and the anion radical of MK establish the nearly pure electron transfer (ET) character of the TICT state. In aprotic solvents, because of the steep slope of the potential energy surface near the Franck-Condon (FC) or LE state region, the LE state is nearly nonemissive at room temperature and fluorescence emission is observed from only the ICT and TICT states. Alternatively, in protic solvents, because of an intermolecular hydrogen-bonding interaction between MK and the solvent, the LE region is more flat and stimulated emission from this state is also observed. However, a stronger hydrogen-bonding interaction between the TICT state and the solvent as well as the closeness between the two potential energy surfaces due to the TICT and the ground states cause the nonradiative coupling between these states to be very effective and, hence, cause the TICT state to be weakly emissive. The multi-exponentiality and strong wavelength-dependence of the kinetics of the relaxation process taking place in the S1 state of MK have arisen for several reasons, such as strong overlapping of transient absorption and stimulated emission spectra of the LE, ICT, and TICT states, which are formed consecutively following photoexcitation of the molecule, as well as the fact that different probe wavelengths monitor different regions of the potential energy surface representing the twisting motion of the excited molecule.
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Affiliation(s)
- Jahur A Mondal
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
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22
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Galievsky VA, Druzhinin SI, Demeter A, Jiang YB, Kovalenko SA, Pérez Lustres L, Venugopal K, Ernsting NP, Allonas X, Noltemeyer M, Machinek R, Zachariasse KA. Ultrafast Intramolecular Charge Transfer and Internal Conversion with Tetrafluoro-aminobenzonitriles. Chemphyschem 2005; 6:2307-23. [PMID: 16273565 DOI: 10.1002/cphc.200500267] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The five 2,3,5,6-tetrafluoro-4-aminobenzonitriles XABN4F with a dimethyl-amino (DMABN4F), diethyl-amino (DEABN4F), azetidinyl (AZABN4F), methyl-amino (MABN4F) or amino (ABN4F) group undergo ultrafast intramolecular charge transfer (ICT) at room temperature, in the polar solvent acetonitrile (MeCN) as well as in the nonpolar n-hexane. ICT also takes place with the corresponding non-fluorinated aminobenzonitriles DMABN, DEABN and AZABN in MeCN, whereas for these molecules in n-hexane only minor (DMABN, DEABN) or no (AZABN) ICT fluorescence is detected. For the secondary (MABN) and primary (ABN) amines, an ICT reaction does not occur, which makes ABN4F the first electron donor/acceptor molecule with an NH(2) group for which ICT is observed. The ICT state of the XABN4Fs has a dipole moment of around 14 D, clearly smaller than that of DMABN (17 D). This difference is attributed to the electron withdrawing from the CN group to the phenyl ring, exerted by the four F-substituents. The reaction from the initially prepared locally excited (LE) to the ICT state in n-hexane proceeds in the sub-picosecond time range: 0.35 ps (DMABN4F), 0.29 ps (DEABN4F) and 0.13 ps (AZABN4F), as determined from femtosecond transient absorption measurements. In the highly polar solvent MeCN, an ICT reaction time of around 90 fs is observed for all five XABN4Fs, irrespective of the nature of their amino group. This shows that with these molecules in MeCN the ICT reaction rate is limited by the solvent dielectric relaxation time of MeCN, for which a value of around 90 fs has been reported. It is therefore concluded that, during this ultrashort ICT reaction, a large-amplitude motion such as a full 90 degrees twist of the amino group is unlikely to occur in the XABN4Fs. The ICT state of the XABN4Fs is strongly quenched via internal conversion (IC), with a lifetime tau'(0) (ICT) down to 3 ps, possibly by a reaction passing through a conical intersection made accessible due to a deformation of the phenyl group by out-of-plane motions induced by vibronic coupling between low-lying pisigma* and pipi* states in the XABN4Fs.
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Affiliation(s)
- Victor A Galievsky
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany
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23
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Druzhinin SI, Ernsting NP, Kovalenko SA, Lustres LP, Senyushkina TA, Zachariasse KA. Dynamics of Ultrafast Intramolecular Charge Transfer with 4-(Dimethylamino)benzonitrile in Acetonitrile. J Phys Chem A 2005; 110:2955-69. [PMID: 16509618 DOI: 10.1021/jp054496o] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The kinetics of the intramolecular charge-transfer (ICT) reaction of 4-(dimethylamino)benzonitrile (DMABN) in the polar solvent acetonitrile (MeCN) is investigated by fluorescence quantum yield and picosecond time-correlated single photon counting (SPC) experiments over the temperature range from -45 to +75 degrees C, together with femtosecond Sn <-- S1 transient absorption measurements at room temperature. For DMABN in MeCN, the fluorescence from the locally excited (LE) state is strongly quenched, with an unquenched to quenched fluorescence quantum yield ratio of 290 at 25 degrees C. Under these conditions, even very small amounts of the photoproduct 4-(methylamino)benzonitrile (MABN) severely interfere, as the LE fluorescence of MABN is in the same spectral range as that of DMABN. The influence of photoproduct formation could be overcome by a simultaneous analysis of the picosecond and photostationary measurements, resulting in data for the activation barriers Ea (5 kJ/mol) and Ed (32 kJ/mol) of the forward and backward ICT reaction as well as the ICT reaction enthalpy and entropy: DeltaH (-27 kJ/mol) and DeltaS [-38 J/(mol K)]. The reaction hence takes place over a barrier, with double-exponential fluorescence decays, as to be expected in a two-state reaction. From femtosecond transient absorption down to 200 fs, the LE and ICT excited state absorption (ESA) spectra of DMABN in n-hexane (LE) and in MeCN (LE and ICT) and also of 4-aminobenzonitrile in MeCN (LE) are obtained. For DMABN in MeCN, the quenching of the LE and the rise of the ICT ESA bands occurs with a single characteristic time of 4.1 ps, the same as the ICT reaction time found from the picosecond SPC experiments at 25 degrees C. The sharp ICT peak at 320 nm does not change its spectral position after a pump-probe delay time of 200 fs, which suggests that large amplitude motions do not take place after this time. The increase with time in signal intensity observed for the LE spectrum of DMABN in n-hexane between 730 and 770 nm, is attributed to solvent cooling of the excess excitation energy and not to an inverse ICT --> LE reaction, as reported in the literature.
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Affiliation(s)
- Sergey I Druzhinin
- Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany.
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Photophysical properties of pyrrolobenzenes with different linking and substitution pattern: The transition between charge transfer states with large (MICT) and small (TICT) resonance interaction. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.06.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Xu X, Cao Z, Zhang Q. Theoretical study of photoinduced singlet and triplet excited states of 4-dimethylaminobenzonitrile and its derivatives. J Chem Phys 2005; 122:194305. [PMID: 16161571 DOI: 10.1063/1.1895673] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Singlet and triplet low-lying states of the 4-dimethylaminobenzonitrile and its derivatives have been studied by the density functional theory and ab initio methodologies. Calculations reveal that the existence of the methyl groups in the phenyl ring and the amino twisting significantly modify properties of their excited states. A twisted singlet intramolecular charge-transfer state can be accessed through decay of the second planar singlet excited state with charge-transfer character along the amino twisting coordinate or by an intramolecular charge-transfer reaction involved with a locally first excited singlet state. Plausible charge-transfer triplet states and intersystem crossing processes among singlet and triplet states have been explored by spin-orbit coupling calculations. The intersystem crossing process was predicted to be the dominant deactivation channel of the photoexcited 4-dimethylaminobenzonitrile.
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Affiliation(s)
- Xuefei Xu
- Department of Chemistry, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China
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26
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Davis BN, Abelt CJ. Synthesis and Photophysical Properties of Models for Twisted PRODAN and Dimethylaminonaphthonitrile. J Phys Chem A 2005; 109:1295-8. [PMID: 16833443 DOI: 10.1021/jp046050y] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis and photophysical properties of 7-cyano-3,4-dihydro-2H-1,4-ethano-benzo[g]quinoline and 3,4-dihydro-2H-1,4-ethano-7-propionyl-benzo[g]quinoline are reported. These compounds possess a quinuclidine substructure that locks the tertiary amino group perpendicular to the naphthalene ring. Their excited states are models for the twisted excited states of 2-(dimethylamino)-6-naphthonitrile (DMANN) and 6-propionyl-2-(dimethylamino)naphthlene (PRODAN). In contrast to DMANN and PRODAN, the fluorescence of these twisted derivatives is strongly deactivated in polar solvents. Neither DMANN nor PRODAN likely emit from TICT excited states.
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Affiliation(s)
- Brittany N Davis
- Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795, USA
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Dahl K, Biswas R, Ito N, Maroncelli M. Solvent Dependence of the Spectra and Kinetics of Excited-State Charge Transfer in Three (Alkylamino)benzonitriles. J Phys Chem B 2005; 109:1563-85. [PMID: 16851128 DOI: 10.1021/jp046605p] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Steady-state absorption and emission spectra and emission decay kinetics are reported for 4-aminobenzonitrile (ABN), 4-(1-azetidinyl)benzonitrile (P4C), 4-(1-pyrrolidinyl)benzonitrile (P5C), and 4-(1-piperidinyl)benzonitrile (P6C) in 24 room temperature solvents. In solvents of modest to high polarity, P4C, P5C, and P6C exhibit dual fluorescence and emission decays characteristic of the transformation from an initially prepared (LE) state to a more polar charge transfer (CT) state, whereas ABN does not undergo this reaction. The frequencies of the steady-state absorption and emission spectra of all of these solutes can be rationalized using a dielectric continuum description of the solvent and considering only the minima on the reactive surfaces, which are assumed to involve both an intramolecular (twisting) and a solvation coordinate. Characteristics of the gas-phase solutes deduced from this analysis are in good agreement with electronic structure calculations and indicate that differences in their spectra mainly reflect differences in the relative energies of the gas-phase LE and CT states. The relative yields of LE and CT emission are not described as satisfactorily by this model, and reasons for this failure are discussed. The kinetics of the LE --> CT reaction vary considerably with solute and solvent. In many solvents, the emission decays of P4C are reasonably described by a simple two-state kinetic scheme with time-independent rate constants. In P5C and P6C multiexponential decays are observed that reflect time-dependent shifts of the component spectra as well as time-dependent reaction rates. A simplified analysis of these complex dynamics provides estimates for both the free energy change Delta(r)G and (average) LE --> CT rate constant k(f) for a wide range of solute and solvent combinations. The driving force for reaction (-Delta(r)G) follows the order P6C > P5C > P4C and increases with increasing solvent polarity. The reaction rates are correlated to Delta(r)G and follow the opposite trend. The relationships observed between k(f) and Delta(r)G suggest that static solvent effects, i.e., barrier height changes, are the primary determinants of the solvent dependence in P4C. Correlations between barrier-corrected rates and solvation times suggest that dynamical solvent effects contribute substantially to the solvent dependence of the rates in P5C, and especially P6C.
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Affiliation(s)
- K Dahl
- Department of Chemistry, Penn State University, University Park, PA 16802, USA
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Yoshizawa T, Iwaki Y, Osaka N, Nakabayashi T, Zachariasse KA, Ohta N. External Electric Field Effects on Absorption, Fluorescence and Phosphorescence Spectra of 4-(Dimethylamino)benzonitrile in a Polymer Film. J Phys Chem B 2004. [DOI: 10.1021/jp040012x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tomokazu Yoshizawa
- Research Institute for Electronic Science (RIES), Hokkaido University, Sapporo 060-0812, Japan, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan, and Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany
| | - Yuji Iwaki
- Research Institute for Electronic Science (RIES), Hokkaido University, Sapporo 060-0812, Japan, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan, and Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany
| | - Naoki Osaka
- Research Institute for Electronic Science (RIES), Hokkaido University, Sapporo 060-0812, Japan, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan, and Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany
| | - Takakazu Nakabayashi
- Research Institute for Electronic Science (RIES), Hokkaido University, Sapporo 060-0812, Japan, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan, and Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany
| | - Klaas A. Zachariasse
- Research Institute for Electronic Science (RIES), Hokkaido University, Sapporo 060-0812, Japan, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan, and Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany
| | - Nobuhiro Ohta
- Research Institute for Electronic Science (RIES), Hokkaido University, Sapporo 060-0812, Japan, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan, and Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany
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29
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Amini A, Harriman A. A Quantum Chemical Study of Intramolecular Charge Transfer in a Closely-Spaced, Donor−Acceptor Molecule. J Phys Chem A 2004. [DOI: 10.1021/jp037039l] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Ata Amini
- Department of Chemistry, Molecular Photonics Laboratory, Bedson Building, University of Newcastle, Newcastle upon Tyne, NE1 7RU, United Kingdom
| | - Anthony Harriman
- Department of Chemistry, Molecular Photonics Laboratory, Bedson Building, University of Newcastle, Newcastle upon Tyne, NE1 7RU, United Kingdom
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Lobo BC, Abelt CJ. Does PRODAN Possess a Planar or Twisted Charge-Transfer Excited State? Photophysical Properties of Two PRODAN Derivatives. J Phys Chem A 2003. [DOI: 10.1021/jp036013r] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Bethany C. Lobo
- Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795
| | - Christopher J. Abelt
- Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795
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Grabowski ZR, Rotkiewicz K, Rettig W. Structural Changes Accompanying Intramolecular Electron Transfer: Focus on Twisted Intramolecular Charge-Transfer States and Structures. Chem Rev 2003; 103:3899-4032. [PMID: 14531716 DOI: 10.1021/cr940745l] [Citation(s) in RCA: 2251] [Impact Index Per Article: 107.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ma C, Kwok WM, Matousek P, Parker AW, Phillips D, Toner WT, Towrie M. Excited States of 4-Aminobenzonitrile (ABN) and 4-Dimethylaminobenzonitrile (DMABN): Time-resolved Resonance Raman, Transient Absorption, Fluorescence, and ab Initio Calculations. J Phys Chem A 2002. [DOI: 10.1021/jp012765e] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C. Ma
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - W. M. Kwok
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - P. Matousek
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - A. W. Parker
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - D. Phillips
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - W. T. Toner
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - M. Towrie
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
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Dobkowski J, Rettig W, Waluk J. Intramolecular charge-transfer properties of a molecule with a large donor group: the case of 4′-(pyren-1-yl)benzonitrile. Phys Chem Chem Phys 2002. [DOI: 10.1039/b204749g] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ma C, Kwok W, Matousek P, Parker A, Phillips D, Toner W, Towrie M. Resonance Raman study of ring deuterated 4-dimethylaminobenzonitrile (DMABN-d4): the ground, ICT and triplet states. J Photochem Photobiol A Chem 2001. [DOI: 10.1016/s1010-6030(01)00512-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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35
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Goez M, Zubarev V. Double Photoionization of Dimethylaminobenzonitrile in Solution: A Three-Quantum Process with Intervening Chemical Step. Angew Chem Int Ed Engl 2001; 40:2867-2869. [DOI: 10.1002/1521-3773(20010803)40:15<2867::aid-anie2867>3.0.co;2-u] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2001] [Indexed: 11/07/2022]
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36
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Goez M, Zubarev V. Doppelte Photoionisation von Dimethylaminobenzonitril in Lösung: ein Dreiquantenprozess mit chemischem Zwischenschritt. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3757(20010803)113:15<2948::aid-ange2948>3.0.co;2-q] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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37
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Ma C, Kwok WM, Matousek P, Parker AW, Phillips D, Toner WT, Towrie M. Time-Resolved Study of the Triplet State of 4-dimethylaminobenzonitrile (DMABN). J Phys Chem A 2001. [DOI: 10.1021/jp004497a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C. Ma
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - W. M. Kwok
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - P. Matousek
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - A. W. Parker
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - D. Phillips
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - W. T. Toner
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - M. Towrie
- Department of Chemistry, Imperial College, Exhibition Road, London SW7 2AY, UK, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, UK, and Department of Physics, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
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Kwok WM, Ma C, Matousek P, Parker AW, Phillips D, Toner WT, Towrie M, Umapathy S. A Determination of the Structure of the Intramolecular Charge Transfer State of 4-Dimethylaminobenzonitrile (DMABN) by Time-Resolved Resonance Raman Spectroscopy. J Phys Chem A 2001. [DOI: 10.1021/jp003705w] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- W. M. Kwok
- Department of Chemistry, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AY, U.K.; Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, U.K.; Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, U.K.; and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
| | - C. Ma
- Department of Chemistry, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AY, U.K.; Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, U.K.; Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, U.K.; and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
| | - P. Matousek
- Department of Chemistry, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AY, U.K.; Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, U.K.; Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, U.K.; and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
| | - A. W. Parker
- Department of Chemistry, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AY, U.K.; Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, U.K.; Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, U.K.; and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
| | - D. Phillips
- Department of Chemistry, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AY, U.K.; Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, U.K.; Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, U.K.; and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
| | - W. T. Toner
- Department of Chemistry, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AY, U.K.; Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, U.K.; Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, U.K.; and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
| | - M. Towrie
- Department of Chemistry, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AY, U.K.; Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, U.K.; Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, U.K.; and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
| | - S. Umapathy
- Department of Chemistry, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AY, U.K.; Central Laser Facility, CLRC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, U.K.; Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, U.K.; and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
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Kwok W, Ma C, Matousek P, Parker A, Phillips D, Toner W, Towrie M. Time-resolved resonance Raman spectra of the intramolecular charge transfer state of DMABN. Chem Phys Lett 2000. [DOI: 10.1016/s0009-2614(00)00436-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kwok WM, Ma C, Phillips D, Matousek P, Parker AW, Towrie M. Picosecond Time-Resolved Study of 4-Dimethylaminobenzonitrile in Polar and Nonpolar Solvents. J Phys Chem A 2000. [DOI: 10.1021/jp9927606] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Bulliard C, Allan M, Wirtz G, Haselbach E, Zachariasse KA, Detzer N, Grimme S. Electron Energy Loss and DFT/SCI Study of the Singlet and Triplet Excited States of Aminobenzonitriles and Benzoquinuclidines: Role of the Amino Group Twist Angle. J Phys Chem A 1999. [DOI: 10.1021/jp990922s] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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