Observation of Nitrogen-Bearing Organic Molecules from Reactions of Nitrogen Atoms with Hydrocarbons: A Crossed Beam Study of N(2D) + Ethylene

The reaction of excited atomic nitrogen, N( 2 D), with the simplest alkene, C 2 H 4, has been investigated under single-collision conditions in crossed beam experiments with mass spectrometric detection. The experimental results clearly show that the N/H exchange channel leading to compounds of gross formula C 2 H 3 N is the main reaction pathway and that the reaction proceeds through the formation of a bound intermediate. The title reaction may well be regarded as a good candidate to account for the formation of acetonitrile, CH 3 CN, in extraterrestrial environments such as the dense atmosphere of Saturn's moon Titan where the ultimate fate of product isomers other than acetonitrile itself, that is 2 H -azirine, H 2 C(N)CH, and ketene imine, CH 2 C NH, is expected to be tautomerization to the most stable structure of acetonitrile.