University of Illinois Urbana-Champaign

Slow photoelectron velocity-map imaging (sevi) spectroscopy of cryo-cooled anions

Weichman, Marissa L.

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1087421.pptx
2963.pdf

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https://hdl.handle.net/2142/100796

Description

Title
Slow photoelectron velocity-map imaging (sevi) spectroscopy of cryo-cooled anions
Author(s)
Weichman, Marissa L.
Contributor(s)
  • Neumark, Daniel
  • DeVine, Jessalyn A.
  • Kim, Jongjin B.
Issue Date
2018-06-22
Keyword(s)
Comparing theory and experiment
Date of Ingest
  • 2018-08-17T16:09:47Z
  • 2018-12-12T22:36:19Z
Abstract
Slow photoelectron velocity-map imaging spectroscopy of cryogenically-cooled anions (cryo-SEVI) is a powerful technique for elucidating the vibrational and electronic structure of exotic neutral species. SEVI is a high-resolution variant of anion photoelectron imaging that yields spectra with energy resolution as high as 1 cm−1 . The preparation of cold anions eliminates hot bands and narrows rotational envelopes, enabling the acquisition of well-resolved photoelectron spectra for complex and spectroscopically challenging species.1,2 Recently, cryo-SEVI has been applied as a spectroscopic probe of transition state dynamics on neutral reactive surfaces, through photodetachment of a bound anion similar in geometry to the desired transition state. In the benchmark F + H2 reaction, we probe the transition state region through detachment of FH− 2 and directly observe new reactive resonances. Comparison to new theory allows for the assignment of resonances associated with quasi-bound states of the transition state and products.3 We also report spectra of the F + CH3OH hydrogen abstraction reaction through photodetachment of the CH3OHF− van der Waals cluster. We gain insight into the energetics and vibrational structure of transient complexes along the reaction coordinate of this complex polyatomic system.4 Finally, we report a new cryo-SEVI study of vinylidene (H2CC), a high energy isomer of acetylene, which is accessed directly through detachment of H2CC−. We find spectroscopic evidence that the isomerization of vinylidene to acetylene is highly state-specific, with excitation of the ν6 in-plane rocking mode resulting in appreciable tunneling-facilitated mixing with highly vibrationally excited states of acetylene.5
Publisher
International Symposium on Molecular Spectroscopy
Type of Resource
text
Genre of Resource
Conference Paper / Presentation
Language
eng
Permalink
http://hdl.handle.net/2142/100796
DOI
10.15278/isms.2018.FC04
Copyright and License Information
Copyright 2018 Marissa L. Weichman

Owning Collections

Abstracts & Presentations - 2018 International Symposium on Molecular Spectroscopy PRIMARY