title: Stable doubly charged positive molecular ions formed by direct attachment of alpha particles to HCN and HNC.
abstract: The existence of [HeNCH](2+) and [HeCNH](2+) is examined by reliable high-level ab initio methods. It is shown that both species are metastable with respect to the proton loss process, but the activation barriers are high enough to accommodate several resonant states. Their estimated lifetimes are practically infinite for v<3, implying that the attachment of alpha particles to HNC and HCN yields kinetically stable dications. This could be an important factor in the cyanide chemistry in interstellar and comet environments.
authors.affiliation: Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
authors.forename: Alicia
authors.initials: A
authors.lastname: Palacios
authors.forename: Fernando
authors.initials: F
authors.lastname: Martín
authors.forename: Otilia
authors.initials: O
authors.lastname: Mó
authors.forename: Manuel
authors.initials: M
authors.lastname: Yáñez
authors.forename: Zvonimir B
authors.initials: ZB
authors.lastname: Maksić