Jacob’s ladder

[Olivier N]

Jacob’s ladder is a ‘ladder’ because it has five rungs. Firstly, it uses LDA (local density approximation). Above that, it uses GGA (generalized gradient approximation), where the electron density gets extended by its gradient. The third rung would be meta-GGA’s, where the kinetic energy density is introduced. The fourth rung extends this further by treating the exchange exactly, and the fifth rung refines the correlation by partly evaluating it in exact form.

[Author]

Posts