Ab initio SCF study of the molecular structures and relative stabilities of the C2H4N+ cation isomers

Abstract

The optimized molecular geometries and relative stabilities of isomers of the C₂H₄N⁺ cations have been determined by ab initio SCF calculations using the 3-21G and 6-31G** basis sets. The N-protonated CH₃CN species (CH₃–CNH⁺) is the most stable among the isomers considered, and this species is found to be the reaction product of the association reaction, CH₃⁺+ HCN, determined by mass spectrometry. The protonation of the neutral C₂H₃N isomers and the isomerization and dissociation of the C₂H₄N⁺ cationic isomers are discussed.