Valence anions of cyanoacetylene, HCCCN-, are synthesized by the 1,2 -H2+ abstraction reaction of O- with acrylonitrile, H2 C=CHCN, while the competing 1,1 -H2+ channel of the same reaction yields the cyanovinylidene anions, CCHCN-. The key to the formation of the elusive, adiabatically weakly bound HCCCN- is the bent -̇C = ̇C-Cskeleton of the reactant. The photoelectron spectrum of HCCCN -, measured by means of photoelectron imaging at 532 nm, consists of a broad structureless band with a vertical detachment energy of 1.04±0.05 eV. The observed anions are stable counterparts of the low-lying anionic resonances of cyanoacetylene, which may contribute (by way of dissociative attachment) to the formation of carbon-rich and CN-containing negative ions in extraterrestrial environments.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry