Fluorescence from the 1 1B
 u state of t
 r
 a
 n
 s,t
 r
 a
 n
 s-1,3,5,7-octatetraene in a free jet

Heimbrook, L. A.; Kohler, Bryan E.; Levy, Irvin J.

doi:10.1063/1.447888

Cited by 67 publications

(39 citation statements)

References 12 publications

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“…Methyl groups are known to stabilize the S 2 (1 1 B u + ) states of polyenes. 28,29,44–46,49,50 For example, measurements of the S 0 (1 1 A g – ) → S 2 (1 1 B u + ) transition energy of octatetraene (no terminal methyl groups) from supersonic jet studies give a (0–0) of 35 553 ± 5 cm –1 . 44,45,51 Decatetraene isolated in a supersonic jet has a S 0 → S 2 electronic origin of 34 783 ± 3 cm –1 , 28,29 giving a 770 cm –1 difference between the S 0 → S 2 transition energies of octatetraene and decatetraene.…”

Section: Resultsmentioning

confidence: 99%

Energies of Low-Lying Excited States of Linear Polyenes

et al. 2008

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Room temperature absorption and emission spectra of the all-trans isomers of decatetraene, dodecapentaene, tetradecahexaene, and hexadecaheptaene have been obtained in a series of nonpolar solvents. The resolved vibronic features in the optical spectra of these model systems allow the accurate determination of S0 (11Ag-) → S2 (11Bu+) and S1 (21Ag–) → S0 (11Ag–) electronic origins as a function of solvent polarizability. These data can be extrapolated to predict the transition energies in the absence of solvent perturbations. The effects of the terminal methyl substituents on the transition energies also can be estimated. Franck–Condon maxima in the absorption and emission spectra were used to estimate differences between S0 (11Ag–) → S1 (21Ag–) and S0 (11Ag–) → S2 (11Bu+) electronic origins and “vertical” transition energies. Experimental estimates of the vertical transition energies of unsubstituted, all-trans polyenes in vacuum as a function of conjugation length are compared with long-standing multireference configuration interaction (MRCI) treatments and with more recent ab initio calculations of the energies of the 21Ag– (S2) and 11Bu+ (S2) states.

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Section: Resultsmentioning

confidence: 99%

Energies of Low-Lying Excited States of Linear Polyenes

et al. 2008

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“…22 Heimbrook et al measured the S 2 -S 0 emission in a supersonic expansion and estimated an S 2 lifetime of 100-300 ps. 27 Leopold et al reported a 18 cm -1 line width for the S 0 -S 2 (0-0) transition in the gas phase. 28 This gives a nonradiative lifetime of 300 fs.…”

Section: Introductionmentioning

confidence: 98%

Excited-State Dynamics of all-trans-1,3,5,7-Octatetraene in Solution. Direct Observation of Internal Conversion from the S₂ to S₁ State and Relaxation Processes in the S₁ State

et al. 2001

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Femtosecond transient absorption spectroscopy was used to study the excited-state dynamics of the S 2 (1 1 B u ) state all-trans-1,3,5,7-octatetraene in solution. The sample was excited at 267 nm and probed at eleven different wavelengths from 340 to 540 nm. Combined with the picosecond fluorescence spectroscopy, this study allows direct observation of the initial excited-state dynamics of all-trans-1,3,5,7-octatetraene and the subsequent relaxation process to the ground state. Transient absorption signals decaying on time scales of about 0.4 ps were seen at wavelengths longer than 480 nm. These absorptions are assigned to an S n -S 2 transition, indicating that internal conversion from the S 2 to S 1 state takes place on a 400-fs time scale. The transient absorption signals observed at shorter wavelengths, which correspond to the S n -S 1 transition, decay on a picosecond to subnanosecond time scale. A weak fluorescence at about 300-350 nm, originating from the S 2 state, and a strong fluorescence at about 350-500 nm, from the S 1 state, were observed. The time profile of the S 2 fluorescence signal is almost equal to the instrument response function, and the lifetime is estimated to be faster than 5 ps. This observation is consistent with the results of transient absorption signals. The S 1 fluorescence signal consists of two decay components. The average lifetimes are 0.88 ns in acetonitrile and 2.0 ns in n-hexane. Nonexponential decay of the fluorescence may result from an equilibrium mixture of the fluorescent state and the conformationally relaxed state. The fluorescence intensity ratio of S 2 to S 1 in solution is much different from that observed in the gas phase. This means that the efficiency of internal conversion increases significantly in solution because of the solute-solvent interactions that are absent in the gas phase. We discuss differences in the excited-state dynamics between 1,3,5-hexatriene and 1,3,5,7-octatetraene.

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“…For the first four systems ͑up to five double bonds͒, the experimental transition energies in gas phase are known. [11][12][13][14][15][16][17][18][19] Table IV reports the experimental as well as the calculated vertical transition energies. Figure 3 shows the shift in the transition energies with respect to butadiene.…”

Section: Polyenesmentioning

confidence: 99%

On the difference between the transition properties calculated with linear response- and equation of motion-CCSD approaches

Caricato

Trucks

Frisch

2009

The Journal of Chemical Physics

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Articles you may be interested in On the difference between the transition properties calculated with linear response-and equation of motion-CCSD approachesIn this work, we quantitatively investigate the difference between the linear response ͑LR͒ and the equation of motion ͑EOM͒ coupled cluster ͑CC͒ approaches in the calculation of transition properties, namely, dipole and oscillator strengths, for the most widely used truncated CC wave function, which includes single and double excitation operators. We compare systems of increasing size, where the size-extensivity may be important. Our results suggest that, for small molecules, the difference is small even with large basis sets. The difference increases with the size of the system, but it is numerically small until hundreds of electron pairs are correlated. Although these calculations may be possible in a few years, at present the EOM approach is more advantageous, albeit more approximate, because it is computationally less demanding.

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Fluorescence from the 1 1B u state of t r a n s,t r a n s-1,3,5,7-octatetraene in a free jet

Cited by 67 publications

References 12 publications

Energies of Low-Lying Excited States of Linear Polyenes

Energies of Low-Lying Excited States of Linear Polyenes

Excited-State Dynamics of all-trans-1,3,5,7-Octatetraene in Solution. Direct Observation of Internal Conversion from the S₂ to S₁ State and Relaxation Processes in the S₁ State

On the difference between the transition properties calculated with linear response- and equation of motion-CCSD approaches

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Fluorescence from the 1 1B u state of t r a n s,t r a n s-1,3,5,7-octatetraene in a free jet

Cited by 67 publications

References 12 publications

Energies of Low-Lying Excited States of Linear Polyenes

Energies of Low-Lying Excited States of Linear Polyenes

Excited-State Dynamics of all-trans-1,3,5,7-Octatetraene in Solution. Direct Observation of Internal Conversion from the S2 to S1 State and Relaxation Processes in the S1 State

On the difference between the transition properties calculated with linear response- and equation of motion-CCSD approaches

Contact Info

Product

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Excited-State Dynamics of all-trans-1,3,5,7-Octatetraene in Solution. Direct Observation of Internal Conversion from the S₂ to S₁ State and Relaxation Processes in the S₁ State