Görling–Levy perturbation theory

Görling–Levy perturbation theory (GLPT) in Kohn–Sham (KS) density functional theory (DFT) is the analogue to what Møller–Plesset perturbation theory (MPPT) is in Hartree–Fock (HF) theory. Its basis is Rayleigh–Schrödinger perturbation theory (RSPT) and the adiabatic connection (AC).

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