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Ring-opening reaction of a trifluorinated indolylfulgide: mode-specific photochemistry after pre-excitation.

ABSTRACT: The ring-opening reaction of a trifluorinated indolylfulgide has been studied as a function of temperature and optical pre-excitation where it was found that reaction times decreased as temperature increased from 10.3 ps at 12 degrees C to 7.6 ps at 60 degrees C. Simultaneously, the quantum yields for the ring-opening reaction grew from 3.1% (12 degrees C) to 5.0% (60 degrees C). When the reaction was started from a non-equilibrium state generated by a directly preceding ring-closure process, the ring-opening reaction became faster and the quantum efficiency increased by more than a factor of three. Analysis of the experimental results points to mode-specific photochemistry in that the promoting, photochemically active modes of the photoreaction are efficiently excited by the directly preceding ring-closure reaction.

SUBMITTER: Draxler S

PROVIDER: S-EPMC2872927 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Ring-opening reaction of a trifluorinated indolylfulgide: mode-specific photochemistry after pre-excitation.

Draxler Simone S Brust Thomas T Malkmus Stephan S DiGirolamo Jessica A JA Lees Watson J WJ Zinth Wolfgang W Braun Markus M

Physical chemistry chemical physics : PCCP 20090402 25

The ring-opening reaction of a trifluorinated indolylfulgide has been studied as a function of temperature and optical pre-excitation where it was found that reaction times decreased as temperature increased from 10.3 ps at 12 degrees C to 7.6 ps at 60 degrees C. Simultaneously, the quantum yields for the ring-opening reaction grew from 3.1% (12 degrees C) to 5.0% (60 degrees C). When the reaction was started from a non-equilibrium state generated by a directly preceding ring-closure process, th ...[more]

PMID: 19562131

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