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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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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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Saltiel J, Wang S. The photochemistry and photophysics of all-trans-1,4-diindanylidenyl-2-butene, a rigid analogue of all-trans-1,6-diphenyl-1,3,5-hexatriene. Photochem Photobiol Sci 2006; 5:883-95. [PMID: 17019466 DOI: 10.1039/b608065k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
all-trans-1,4-Diindanylidenyl-2-butene (ttt-stiff-5-DPH), a torsionally constrained analogue of all-trans-1,6-diphenyl-1,3,5-hexatriene (ttt-DPH), was synthesized and studied in order to evaluate the role of phenyl-vinyl torsional motions in the photophysical and photochemical responses of the DPH chromophore. Spectroscopic and photoisomerization measurements reveal that the behavior of the rigid DPH analogue is very similar to that of the parent DPH. This similarity is obtained despite the fact that the alkyl substitution from the five-membered rings selectively lowers the energy of the 1 (1)B(u)* state, leading to inversion of the order of the 1 (1)B(u)* and 2 (1)A(g)* energy levels in hydrocarbon solvents. In stiff-5-DPH, as in DPH, an increase in solvent polarity enhances terminal over central bond photoisomerization. Analyses of fluorescence and photoisomerization quantum yields show that, as in DPH, the torsional relaxation channel on the singlet excited state manifold is inefficient, falling far short of accounting for all radiationless decay. Significant (approximately 50 and 80% of all singlet decay in Bz and AN, respectively), photochemically unproductive, radiationless decay channels exist in both molecules. Competing one bond photoisomerizations give the two major photoproducts: tct-stiff-5-DPH and ctt-stiff-5-DPH. They were isolated in pure form and were spectroscopically characterized. Biacetyl-sensitization was used to study the behavior of the stiff-5-DPH triplet state. As in the parent DPH, stiff-5-DPH triplets undergo relatively efficient concentration dependent geometric photoisomerization.
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Affiliation(s)
- Jack Saltiel
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, USA.
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Turek AM, Krishnamoorthy G, Sears DF, Garcia I, Dmitrenko O, Saltiel J. Resolution of Three Fluorescence Components in the Spectra of all-trans-1,6-Diphenyl-1,3,5-hexatriene under Isopolarizability Conditions. J Phys Chem A 2004; 109:293-303. [PMID: 16833347 DOI: 10.1021/jp045201u] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
all-trans-1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescence in solution consists of emissions from the S1 (2(1)A(g)) and S2 (1(1)B(u)) states of the s-trans,s-trans conformer (s-t-DPH) and emission from the S1 state of the s-cis,s-trans conformer (s-c-DPH). The contribution of s-c-DPH fluorescence increases upon excitation at longer wavelengths, and both minor emissions, s-c-DPH and 1(1)B(u) s-t-DPH fluorescence, contribute more at higher temperatures (Ts). Resolution of a spectrothermal matrix of DPH fluorescence spectra by principal component analysis with self-modeling (PCA-SM) is hampered by T-dependent changes in the spectra of the individual components. We avoided differential polarizability-dependent spectral shifts by measuring the spectra in n-alkanes (Cn, C8 to C16 with n even) at T values selected to keep the index of refraction constant, hence under isopolarizability conditions. Compensation of the spectra for T-induced broadening allowed resolution of the spectral matrix into its three components. The optimum van't Hoff plot gives Delta H = 2.83 kcal/mol for s-c-DPH/s-t-DPH equilibration, somewhat smaller than the 3.4 kcal/mol calculated value, and the optimum Boltzmann distribution law plot gives Delta E(ab) = 4.09 kcal/mol for 1(1)B(u)/2(1)A(g) equilibration. The 1(1)B(u) fluorescence spectrum bears mirror-image symmetry with the DPH absorption spectrum, and the energy gap, 1431 cm(-1), is consistent with the 1615 cm(-1) difference between the lowest energy bands in the 1(1)B(u) and 2(1)A(g) fluorescence spectra. The results give V(ab) = 198 +/- 12 cm(-1) for the vibronic matrix coupling element between the 2(1)A(g) and 1(1)B(u) states. Fluorescence quantum yields and lifetimes under isopolarizability conditions reveal an increase in the effective radiative rate constant of s-t-DPH with increasing T.
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Affiliation(s)
- Andrzej M Turek
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, USA
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Saltiel J, Krishnamoorthy G, Huang Z, Ko DH, Wang S. Photoisomerization of all-trans-1,6-Diphenyl-1,3,5-hexatriene. Temperature and Deuterium Isotope Effects. J Phys Chem A 2002. [DOI: 10.1021/jp021540g] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jack Saltiel
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390
| | | | - Zhennian Huang
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390
| | - Dong-Hoon Ko
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390
| | - Shujun Wang
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390
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Scherer P, Fischer SF. Vibronic couplings and radiationless transitions between the lowest 1Bu and the first excited 2Ag state of linear polyenes. J Photochem Photobiol A Chem 2001. [DOI: 10.1016/s1010-6030(01)00571-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Bersuker IB. Modern aspects of the Jahn-Teller effect theory and applications to molecular problems. Chem Rev 2001; 101:1067-114. [PMID: 11709858 DOI: 10.1021/cr0004411] [Citation(s) in RCA: 426] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- I B Bersuker
- Institute for Theoretical Chemistry, Department of Chemistry & Biochemistry, University of Texas at Austin, Austin, Texas 78712, USA.
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Gilbert T, Fischer I, Chen P. Zero kinetic energy photoelectron spectra of the allyl radical, C3H5. J Chem Phys 2000. [DOI: 10.1063/1.481831] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Werncke W, Hogiu S, Pfeiffer M, Lau A, Kummrow A. Strong S1−S2 Vibronic Coupling and Enhanced Third Order Hyperpolarizability in the First Excited Singlet State of Diphenylhexatriene Studied by Time-Resolved CARS. J Phys Chem A 2000. [DOI: 10.1021/jp992839a] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- W. Werncke
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany
| | - S. Hogiu
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany
| | - M. Pfeiffer
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany
| | - A. Lau
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany
| | - A. Kummrow
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany
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Woywod C, Livingood WC, Frederick JH. S1–S2 vibronic coupling intrans-1,3,5-hexatriene. II. Theoretical investigation of absorption and resonance Raman spectra. J Chem Phys 2000. [DOI: 10.1063/1.480554] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Hogiu S, Werncke W, Pfeiffer M, Lau A. Evidence of strong vibronic coupling in the first excited singlet state of diphenylhexatriene by picosecond CARS spectroscopy. Chem Phys Lett 1999. [DOI: 10.1016/s0009-2614(99)00191-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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