Dissociation and approximations

The channels where the molecule comes apart, and the two reduced models — local and nonlocal — measured against the exact solver.

• NO and F₂ exact-2D VE cross sections (the model port)
• The nonlocal resonance model (NRM)
• H₂⁺ dissociative recombination (the first ionic model)

• NO and F₂ exact-2D VE cross sections (the model port) — NO and F₂, and the local-complex-potential approximation measured against the exact oracle.

• The nonlocal resonance model (NRM) — the rung above the LCP: a nonlocal, energy-dependent kernel that keeps the energy dependence and the nonlocality the LCP throws away. On vibrational excitation it reproduces the exact oracle to better than 0.7 % on both N₂ and F₂ (now its own note, NRM vibrational excitation, filed under the engine section), elastic and first-inelastic alike, and the note argues that is physics rather than luck — an R-independent discrete state carries no derivative couplings, so the model is formally exact and the residual is discretization error. On dissociative attachment it reproduces the oracle on F₂ and on NO; the five-to-eight-order NO “collapse” this page used to report was the exact 2-D oracle’s own volume-T-matrix defect, charged to the model, and is retracted.

• H₂⁺ dissociative recombination (the first ionic model) — dissociative recombination for an ionic target.