NO+ + H2: Potential energy surface and bound state calculations

Highlights: • The first 4D ab initio PES for the intercation of NO⁺ + H₂ has been constructed. • The global minimum was found at R = 5.30 a₀, θ′ = 90°, θ = 113°, and φ = 90°. • Bound states are computed in a straightforward manner. • D₀ = 498.15 cm⁻¹ was found for para-H₂–NO⁺ complex, and of 541.35 cm⁻¹ for ortho-H₂–NO⁺. The first four-dimensional (4D) adiabatic potential energy surface (PES) for the interaction of NO⁺ cation with the H₂ molecule has been accurately determined using the CCSD(T)-F12a method with cc-pVTZ-F12 basis set augmented with mid-bond functions. A detailed characterization of the PES and lowest bound states of the H₂–NO⁺ complex have been provided. The H₂–NO⁺ PES exhibits a single global minimum with a well depth of −824.63 cm⁻¹ corresponding to off-planar structure with the H₂ molecule in a perpendicular orientation to the NO⁺ cation. The solution of the nuclear Schrödinger equation for the bound states gives a zero-point energy corrected dissociation energy of D₀ = 498.15 cm⁻¹ for para-H₂–NO⁺ complex, and of 541.35 cm⁻¹ for ortho-H₂–NO⁺.