Does N2− exist? A coupled-cluster study

Abstract

Potential energy curves of the ground-state N2 molecule and its doublet N2− anion are calculated at the coupled-cluster level with single and double excitations and with noniterative triples [CCSD(T)] as well as with the multireference averaged-quadratic coupled-cluster (MR-AQCC) method. The N2− anion is shown to be temporary and decays to its neutral parent plus a free electron at bond lengths shorter than ≈1.4 and larger than ≈2.5 Å. Thus, the N2− anion exists within the 1.4⩽R(N–N)⩽2.5 Å range at the Born–Oppenheimer approximation.