Theory notes

One note per method: the derivation, the equations, the unit conventions (atomic units throughout), the validation evidence, and the literature it comes from. These are the working notes behind the implementation, so they record limitations and negative results as well as what works.

The notes are grouped into seven sections in the sidebar:

• Discretisation — turning a coordinate into a matrix, and choosing the grid.

• Linear algebra and solvers — the sparse factorizations and eigensolves underneath.

• The scattering engine — the model-independent solver and the time-independent routes.

• Time-dependent routes — the wavepacket route to the same answers.

• Dissociation and approximations — the channels where the molecule comes apart, and the reduced models measured against the exact solver.

• Resonances and levels — quasi-bound states, exactly and approximately.

• Open directions — designed but parked.

Validation harnesses cuts across all of them: what each harness in validation/ gates, and how to run it.

For a per-molecule view — what has been computed on N₂, NO, F₂ and H₂⁺, and which notes report it — start from the Molecules section of the sidebar.