Theoretical study of the N+2 molecular ion

The Equations of Motion method has been applied in the calculation of potential energy curves for the X²Σ⁺_g, A²Π_u and B²Σ⁺_u states of N⁺₂. Results are also reported for a new dissociative ²Σ⁺_g state. The theoretical curves are directly compared with the experimental ones as well as in terms of spectroscopic constants. The applicability of the Equations of Motion method to this type of problem is critically examined and discussed with regard to the choice of basis set, numerical effort and agreement with experiment.