Delocalization of free electron density through phenylene-ethynylene: Structural changes studied by time-resolved infrared spectroscopy

Dmitry Polyansky, Evgeny O. Danilov, Sergey V. Voskresensky, Michael A J Rodgers, Douglas C. Neckers

Research output: Contribution to journalArticle

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Abstract

We have studied the photochemistry of 1,4-bis(2-[4-tert-butylperoxycarbonylphenyl]ethynyl)benzene (1) and tert-butyl 4-(2-{4-[2-(4-phenyloxycarbonylphenyl)-1-ethynyl]phenyl}-1-ethynyl)peroxybenzoate (2). Excitation of 1 and 2 by a 355-nm laser pulse leads to the rapid formation of aroyloxyl radicals. An unpaired electron conjugated with the phenylene-ethynylene core is substantially delocalized over the π-system of the chromophore. The -CC- vibrational frequencies of these radicals are red-shifted relative to 1 and 2 as measured by time-resolved IR spectroscopy. This shift is attributed to the change in the triple bond character due to delocalization of the free electron.

Original languageEnglish
Pages (from-to)13452-13453
Number of pages2
JournalJournal of the American Chemical Society
Volume127
Issue number39
DOIs
Publication statusPublished - Oct 5 2005

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Carrier concentration
Infrared spectroscopy
Spectrum Analysis
Electrons
Photochemistry
Photochemical reactions
Vibrational spectra
Chromophores
Benzene
Laser pulses
Lasers

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Delocalization of free electron density through phenylene-ethynylene : Structural changes studied by time-resolved infrared spectroscopy. / Polyansky, Dmitry; Danilov, Evgeny O.; Voskresensky, Sergey V.; Rodgers, Michael A J; Neckers, Douglas C.

In: Journal of the American Chemical Society, Vol. 127, No. 39, 05.10.2005, p. 13452-13453.

Research output: Contribution to journalArticle

Polyansky, Dmitry ; Danilov, Evgeny O. ; Voskresensky, Sergey V. ; Rodgers, Michael A J ; Neckers, Douglas C. / Delocalization of free electron density through phenylene-ethynylene : Structural changes studied by time-resolved infrared spectroscopy. In: Journal of the American Chemical Society. 2005 ; Vol. 127, No. 39. pp. 13452-13453.
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