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Deuterium Isotope Effect on Internal Conversion of Ethylene Studied by Time-Resolved Photoelectron Spectroscopy
Alexie Boyer1, Alexander Humeniuk1, Shutaro Karashima1
1Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-Ku, Kyoto 606-8502, Japan.
Abstract:
The effect of deuterium isotopes on the internal conversion of ethylene is studied by using extreme ultraviolet time-resolved photoelectron spectroscopy. For deuterium-labeled ethylene, the time scale for ultrafast internal conversion is increased by a factor of approximately √2, in agreement with the results of ab initio multiple spawning calculations, indicating the essential role played by hydrogen motion in the conversion process. Following internal conversion, a metastable species with an electron binding energy of ∼9 eV is produced, and it decays with a time constant similar to that for both isotopologues.
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