SEARCH Articles Figures Tables A posteriori correction to multi-reference Brillouin-Wigner perturbation theory Brillouin-Wigner perturbation Brillouin-Wigner perturbation theory Brillouin-Wigner perturbation theory multi-reference second order Brillouin-Wigner theory Multi-reference Brillouin-Wigner perturbation Multi-reference Brillouin-Wigner perturbation theory for limited configuration interaction Multi-reference perturbation Perturbation theory Brillouin Single-root formulation of multi-reference Brillouin-Wigner perturbation theory