Electronic structure and spectroscopic properties of some low-lying electronic states of neutral and ionic species CN and CN ⁻

Abstract: We probe a new pathway for the formation of smaller anions from the temporary negative ion states (anion resonances) of CnN− (n = 1–3, 5–7) in the circumstellar envelope of IRC+10216. CnN− (n = 1–3, 5–7) anions were collisionally excited to their resonance states and were observed to decay into a variety of smaller anions. The measured kinetic-energy-release distributions for the anionic fragments arising from each of the parent anions indicate a concerted manner of occurrence of these fragments, implying rich dissociation dynamics. and C2N− were found to be dominant fragments of these anions, suggesting their presence in the external layers of IRC+10216 where UV photons penetrate. CnN− (n = 1–3) were also observed to undergo dissociative and nondissociative double-electron detachments, with the former being dominant. The significance of this new pathway in determining the stability and abundance of anions in IRC+10216 is discussed.

TL;DR: In this article, the authors reported long-lived, superexcited cyanide anion yields from the dissociative electron attachment to cyanogen bromide (BrCN).

TL;DR: The detection of negatively charged molecules in the interstellar and circumstellar medium in the past four years has been one of the most impacting surprises in the area of molecular astrophysics and has motivated the interest of astronomers, physicists, and chemists on the study of the spectroscopy, chemical kinetics, and prevalence of molecular anions in different astronomical regions as mentioned in this paper.