SEARCH Articles Figures Tables A posteriori correction to multi-reference Brillouin-Wigner perturbation theory Brillouin-Wigner perturbation theory multi-reference second order Excited states multi-reference perturbation theory Multi-reference Brillouin-Wigner perturbation Multi-reference Brillouin-Wigner perturbation theory Multi-reference Brillouin-Wigner perturbation theory for limited configuration interaction Multi-reference Rayleigh-Schrodinger perturbation theory Multi-reference function perturbation Multi-reference function perturbation expansion Multi-reference perturbation theory Multi-reference perturbation theory correlation Multi-reference second-order perturbation Perturbation expansion, multi-reference Single-root formulation of multi-reference Brillouin-Wigner perturbation theory State-specific multi-reference perturbation theories