Local-density approximation

The local-density approximation, (LDA), is a density functional model in physics, which approximates the electron correlation energy with respect to the local electron density. In this sense, local means that, within the LDA model, the electron correlation at any point in space is a function of the electron density at that point in space only.

The LDA functional is derived from a model assuming that the per-electron exchange-correlation energy at every point in space is equal to the per-electron exchange-correlation energy of a homogeneous electron gas. This model is sometimes known as the Jellium model.