N(4S ∕2D)+N2: accurate ab initio-based DMBE potential energy surfaces and surface-hopping dynamics.

This work gives a full account of the N((4)S∕(2)D)+N(2)((1)Σ(g)(+)) interactions via accurate electronic structure calculations and study of the involved exchange reactions. A 2 × 2 diabatic representation of the potential energy surface is suggested for N(3)((2)A(')), which, combined with the two previously reported adiabatic forms for (2)A(") and another for (4)A("), completes the set of five global potentials required to study the title collisional processes. The trajectory results provide the first N((2)D)+N(2) rate constants, and allow a comparison with the ones for N((4)S)+N(2). Nonadiabatic effects are estimated by surface hopping, and the geometrical phase effect assessed by following the trajectories that encircle the crossing seam.