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The process of dissociative electron attachment to the HC3N molecule is considered using a theoretical approach. Two 2\Pi resonances located, respectively, at 1.089 and 6.373 eV play the major role in the process and are accounted for in the present approach. The cross section for dissociative electron attachment through the two resonances is computed using a model in which the molecular dissociation—occurring after the electron is captured into one of the two resonance states—proceeds along two vibrational degrees of freedom, responsible for dissociation towards the H + C3N− products.
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Electron-induced vibrational excitation and dissociative electron attachment in methyl formate
We probe the low-energy electron collisions with methyl formate HCOOCH 3 , focusing on its resonant states. Experimentally, we (i) use two-dimensional electron energy loss spectroscopy to gain information about the vibrational excitation and (ii) report the absolute dissociative electron attachment cross sections. The electron scattering spectra reveal both the threshold effects due to the long-range electron–molecule interaction and a pronounced π* resonance centered around 2.1 eV. This resonance gives rise to dissociative electron attachment into three different anionic channels, the strongest one being the production of the formate anion. Theoretically, we characterize this resonant state using the complex absorbing potential approach combined with multistate multireference perturbation theory, which predicts its position and width in excellent agreement with the experiment.
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- Award ID(s):
- 1665276
- PAR ID:
- 10202564
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 22
- Issue:
- 2
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 518 to 524
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1039/c9cp05165a
