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Photodissociation of N2O: Triplet states and triplet channel
The Journal of Chemical Physics, 2011The role of triplet states in the UV photodissociation of \documentclass[12pt]{minimal}\begin{document}$\rm N_2O$\end{document}N2O is investigated by means of quantum mechanical wave packet calculations. Global potential energy surfaces are calculated for the lowest two 3A′ and the lowest two 3A′′ states at the multi-reference configuration interaction
Schinke, R. +2 more
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Carotenoid triplet state lifetimes
Journal of Photochemistry and Photobiology B: Biology, 2000Carotene and xanthophyll triplet lifetimes are found to depend on the concentration of the parent molecule. These results account for some of the variations in carotenoid triplet lifetimes reported previously. The rate constants obtained for ground state quenching correlate with the number of conjugated double bonds, the longer chain systems having ...
M, Burke +3 more
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Excited-State Triplet-Triplet Absorption in αNPO
Applied Spectroscopy, 1987Time-resolved excited-state triplet-triplet absorption measurements in αNPO solutions were performed. A concentration quenching effect on the excited absorption and fluorescence spectra, due to excimer formation, was seen. A numerical analysis of the results yielded the rate constants for intersystem crossing, triplet quenching by ...
A. N. Dharamsi, A. B. Hassam
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1976
In our discussion in Chapter 1 of the various photophysical processes which can occur in an organic molecule upon absorption of light, we saw that two types of electronic excited states are possible. The first, initially reached upon excitation, is the singlet, in which the electronic spins remain paired.
Dwaine O. Cowan, Ronald L. Drisko
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In our discussion in Chapter 1 of the various photophysical processes which can occur in an organic molecule upon absorption of light, we saw that two types of electronic excited states are possible. The first, initially reached upon excitation, is the singlet, in which the electronic spins remain paired.
Dwaine O. Cowan, Ronald L. Drisko
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Phosphorescence and Triplet State Energies of Oligothiophenes
The Journal of Physical Chemistry B, 2005The phosphorescence spectra of a series of small oligothiophenes (nT, n = 1-3) incorporating a variety of substituents, end cappers, and functional groups have been recorded for the first time using gated detection in combination with nanosecond excitation in frozen solution at 80 K.
Wasserberg, D. +4 more
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Canadian Journal of Chemistry, 1972
Ketene quenches the phosphorescence of both biacetyl and hexafluoroacetone. Although the quenching of hexafluoroacetone emission is nearly collision-controlled, that of biacetyl is much less efficient. The large difference in the rate constants is attributed to endothermic energy transfer from triplet biacetyl to ketene and exothermic energy transfer ...
John S. E. McIntosh, Gerald B. Porter
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Ketene quenches the phosphorescence of both biacetyl and hexafluoroacetone. Although the quenching of hexafluoroacetone emission is nearly collision-controlled, that of biacetyl is much less efficient. The large difference in the rate constants is attributed to endothermic energy transfer from triplet biacetyl to ketene and exothermic energy transfer ...
John S. E. McIntosh, Gerald B. Porter
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Triplet State of Triphenylamine
Nature, 1969Two transient species with absorption peaks at 5300 and 6100 A have been observed in de-oxygenated solutions of triphenylamine by a flash photolysis technique1,2. The major product at room temperature is said to have been the 6100 A compound, and this was considered to be an “intermediate” from which N-phenyl carbazole was formed in the presence of ...
G. C. TERRY +2 more
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Journal of the Chemical Society, Perkin Transactions 2, 1977
The energy levels of the S1,S2 and T1 states of a range of cyclic and acyclic phenylalkenes have been determined and the structure–excited state energy level relationship examined. The S2(Franck–Condon maximum)–T1(absorption onset) energy gap is a constant for all the systems studied (189.5 ± 4 kJ mol–1). except the severely twisted cis-t-butylstyrene,
Paul M. Crosby +5 more
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The energy levels of the S1,S2 and T1 states of a range of cyclic and acyclic phenylalkenes have been determined and the structure–excited state energy level relationship examined. The S2(Franck–Condon maximum)–T1(absorption onset) energy gap is a constant for all the systems studied (189.5 ± 4 kJ mol–1). except the severely twisted cis-t-butylstyrene,
Paul M. Crosby +5 more
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The triplet state of azobenzene
Chemical Physics Letters, 1981Abstract The quenching rate constants ( k q ) for triplet energy transfer from aromatic hydrocarbons to trans and cis azobenzene have been measured by flash kinetic spectrophotometry. For both isomers the plot log k q versus E T of the donors shows a “non-classical” behaviour.
Sandra Monti +3 more
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