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104-fold isotope effect: Vibrational predissociation in ArDF
Published
Author(s)
S Davis, J T. Farrell, D T. Anderson, David Nesbitt
Abstract
High-resolution sub-Doppler line shapes for ArDf excited into the vDF=1 manifold are recorded using a turnable laser/slit supersonic expantion near-infrared spectrometer. Direct spectroscopic evidence is obtained for vibrational predissociation (τless than or equal to}130 ns), in dramatic contrast with the highly metastable ArHF (vHF=1) species (2.69140 MHz less than or equal to}4.3(8) MHz) observed in bolometry studies. To the best of our knowledge, this represents an unprecedentedly large (>104-fold), inverse isotope effect. Furthermore, a clear dependence of the ArDF predissociation rates on intermolecular mode, excited in combination with the DF stretch, is observed (61(30) ns ≥τVHF+Σbend≥94(60) ns).
Citation
Chemical Physics Letters
Volume
246
Issue
No. 1-2
Pub Type
Journals
Keywords
isotope, vibrational predissociation
Citation
Davis, S.
, Farrell, J.
, Anderson, D.
and Nesbitt, D.
(1996),
104-fold isotope effect: Vibrational predissociation in ArDF, Chemical Physics Letters
(Accessed October 18, 2025)