Low energy electron attachment to cyanamide (NH2CN)

Abstract

Cyanamide (NH2CN) is a molecule relevant for interstellar chemistry and the chemical evolution of life. In the present investigation, dissociative electron attachment to NH2CN has been studied in a crossed electron–molecular beams experiment in the electron energy range from about 0 eV to 14 eV. The following anionic species were detected: NHCN−, NCN−, CN−, NH2−, NH−, and CH2−. The anion formation proceeds within two broad electron energy regions, one between about 0.5 and 4.5 eV and a second between 4.5 and 12 eV. A discussion of possible reaction channels for all measured negative ions is provided. The experimental results are compared with calculations of the thermochemical thresholds of the anions observed. For the dehydrogenated parent anion, we explain the deviation between the experimental appearance energy of the anion with the calculated corresponding reaction threshold by electron attachment to the isomeric form of NH2CN—carbodiimide.

Formation of Negative Ions upon Dissociative Electron Attachment to the Astrochemically Relevant Molecule Aminoacetonitrile

“…Beside CN -, it is the second distinctive anion formed by DEA to aminonitriles. 5 As the EA of NH2 is only 0.77 eV which is significantly lower than the EA of the CN molecule of 3.90 eV (see Table 1), this rather low difference in these two anion intensities additionally support the above explanation of the CNanion formation route. The negative ion of the amino radical (NH2) may be formed via the following reaction channels:…”

“…Recently, we studied the negative ion formation by the dissociative electron attachment to cyanamide. 5 Cyanamide as well as AAN are representatives of a biologically relevant and very important group of aminonitriles. These compounds contain two significant organic groups, namely the amino (NH2) and cyano (CN) groups.…”

Dissociation of methyl formate (HCOOCH3) molecules upon low-energy electron attachment

“…For example, abundant ion yield of the dehydrogenated parent anion was previously observed in DEA to organic acids and glycolaldehyde (Sailer et al 2003;Ptasińska et al 2005b;Pelc et al 2002Pelc et al , 2004Pelc et al , 2005, nitriles (Tanzer et al 2015;Pelc et al 2016), nitrocompounds (Pelc et al 2007) and biomolecules (Denifl et al 2008;Vizcaino et al 2012). As the hydrogen atom could be abstracted from two sites in the methyl formate molecule, the C 2 H 3 O − 2 anion may be formed via two DEA channels.…”

Dissociative electron attachment to the gas-phase nucleobase hypoxanthine

“…The DEA to Hyp was investigated in a high vacuum chamber (base pressure ~8 x 10 -8 mbar) at the Nano-Bio-Physics laboratory in Innsbruck. We have described this instrument in detail in several previous publications [24][25][26][27]. Hyp (C 5 H 4 N 4 O, M = 136 g/mol), a white crystalline powder, was purchased from Sigma-Aldrich (Vienna, Austria) and had a stated purity of ≥ 99%.…”