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Updated: May 16, 2026

Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Vibrationally resolved transition state spectroscopy of the F + H2 and F + CH4 reactions
Tara I Yacovitch1, Etienne Garand, Jongjin B Kim
1Department of Chemistry, University of California, Berkeley, CA 94720, USA.
Abstract:
The transition state regions of the F + para-H2, F + normal-H2, F + CH4 and F + CD4 reactions have been studied by slow electron velocity-map imaging (SEVI) spectroscopy of the anionic precursor clusters para-FH2-, normal-FH2-, FCH4 and FCD4. The F + H2 results improve on previously published photoelectron spectra, resolving a narrow peak that appears in the same position in the para-FH2 and normal-FH2- spectra, and suggesting that additional theoretical treatment is necessary to fully describe and assign the experimental results. A small peak in the para-FH2- results is also identified, matching simulations of a product resonance in the v' = 3 vibrational level. SEVI spectra of the 2P3/2 bands of FCH4- and FCD4- show extended structure from transitions to the entrance valley van der Waals region and the reactant side of the F + CH4 transition state region. Much of this structure is attributed to bending or hindered rotation of the methane moiety and may be a spectroscopic signature of reactive resonances.
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