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arXiv · 2011.13438

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

Guglielmo Panelli·Ali Moradmand·Brandon Griffin·Kyle Swanson·Thorsten Weber·Thomas N. Rescigno·C. William McCurdy·Daniel S. Slaughter·Joshua B. Williams
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Abstract

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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Guglielmo Panelli, Ali Moradmand, Brandon Griffin, Kyle Swanson, Thorsten Weber, Thomas N. Rescigno, C. William McCurdy, Daniel S. Slaughter, Joshua B. Williams. 2020-11-26. Investigating resonant low-energy electron attachment to formamide: dynamics of model peptide bond dissociation and other fragmentation channels. https://doi.org/10.1103/physrevresearch.3.013082

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