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Investigating resonant low-energy electron attachment to formamide: dynamics of model peptide bond dissociation and other fragmentation channels

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 نشر من قبل Daniel Slaughter
 تاريخ النشر 2020
  مجال البحث فيزياء
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We report experimental results on three-dimensional momentum imaging measurements of anions generated via dissociative electron attachment to gaseous formamide. From the momentum images, we analyze the angular and kinetic energy distributions for NH$_2^{-}$, O$^{-}$, and H$^{-}$ fragments and discuss the possible electron attachment and dissociation mechanisms for multiple resonances for two ranges of incident electron energies, from 5.3~eV to 6.8~eV, and from 10.0~eV to 11.5~eV. {it Ab initio} theoretical results for the angular distributions of the NH$_2^{-}$ anion for $sim$6~eV incident electrons, when compared with the experimental results, strongly suggest that one of the two resonances producing this fragment is a $^2$A$$ Feshbach resonance.



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