Experimental and theoretical studies are presented on the reactivity of H2CNH•+ (methanimine) and HCNH2•+ (aminomethylene) with ethene (C2H4). Selective isomer generation is performed via dissociative photoionization of suitable neutral precursors and reactive cross sections and branching ratios are measured as a function of photon and collision energies. Differences between isomers’ reactivity are discussed in light of ab-initio calculations on reaction mechanisms. The main products, for both isomers, are H-elimination, most likely occurring from covalently bound adducts (giving c-CH2CH2CHNH+/ CH2NHCHCH2+) and H• atom transfer to yield H2CNH2+. The astrochemical implications of the results are briefly addressed.
Sundelin D., Ascenzi D., Richardson V., Alcaraz C., Polášek M., Romanzin C., Thissen R., Tosi P., Žabka J., Geppert W. The reactivity of methanimine radical cation (H2CNH•+) and its isomer aminomethylene (HCNH2•+) with C2H4. Chemical Physics Letters 777, 138677 (2021). https://doi.org/10.1016/j.cplett.2021.138677