HN2(2A‘) Electronic Manifold. I. A Global ab Initio Study of First Two States

Abstract

A detailed ab initio multireference configuration interaction calculation with a standard aug-cc-pVTZ basis set is reported for the 12A‘ and 22A‘ states of the title system. The aim is to establish the dissociation scheme of all channels, while revealing the 22A‘/32A‘ seam of conical intersections consistent with the crossings in the diatomic fragments. An ab initio mapping of linear NNH and T-shaped and linear NHN loci of conical intersections is also reported, jointly with a discussion of the topological features associated to a newly reported 22A‘/32A‘ crossing seam.