Isomers and reactivity of C3N+: An experimental study

Article abstract of DOI:10.1021/ja00049a054

The C₃N⁺ ion, generated by electron impact on HC₃N and C₄N₂ and as a product in several ion-molecue reactions, was found to exist in two isomeric forms: CCCN⁺ and cylic C₃N⁺. These forms were distinguished by their different reactivities with a range of neutral reagents in a selected-ion How tube (SIFT). Isomeric identification was made by reference to existing ab initio calculations. The most reactive isomer, CCCN⁺, was the major form (≥90%) of the C₃N⁺ ion from all sources of production examined and was found to undergo collision-rate reactions with most of the neutral molecules studied c-C₃N⁺ was much less reactive, which implies an activation barrier in its reactions as it is the higher energy form. Product distributions are reported for the reactions of CCCN⁺, and rate coefficients for the reactions of both isomers with H₂, CH₄, NH₃, M₂O, N₂, O₂, CO, C₂H₂, HCN, CO₂, and C₂N₂ at 300 ± 5 K are also given.