The reactivity of methanimine radical cation (H2CNH.+) and its isomer aminomethylene (HCNH2.+) with methane

• Experimental and theoretical studies are presented on the reactions of the isomeric radical cations H2CNH+ and HCNH2+ with CH4. Ionic isomers were generated selectively by VUV dissociative photoionization of azetidine and cyclopropylamine precursors respectively. Both exclusively give H2CNH2+ plus CH3 as products, but differences are observed related to a competition between stripping and complex-mediated H-transfer. Astrochemical implications for Titan’s atmosphere are briefly discussed, where the presence of methanimine (H2CNH), a key prebiotic molecule and a potential precursor for tholins, is proposed on the basis of atmospheric models and the observation of CH2NH2+ ions in Cassini mass spectrometric data.

Ämnesord

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Nyckelord

Interstellar medium

Rate constants

Ion-molecule reactions

Astrochemistry

Molecular astrophysics

Titan's atmosphere

Methane activation

Isomer

Methanimine

Aminomethylene

Publikations- och innehållstyp

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