SEARCH Articles Figures Tables Ab Initio Single-Reference Approaches Active-space single-reference Brillouin-Wigner coupled cluster single-root multi-reference Brillouin-Wigner coupled cluster theory single-reference Brillouin-Wigner perturbation theory single-reference Clusters single reference many-body Configuration interaction theory single-reference Brillouin-Wigner Coupled-cluster method single-reference Fock space single-reference Hartree-Fock theory single-reference methods Multi-reference Brillouin-Wigner coupled cluster single- and Multi-reference Brillouin-Wigner coupled-cluster theory, single-root Multi-reference Brillouin-Wigner single-root Perturbation expansion, single-reference Perturbation expansion, single-reference function Single reference Brillouin-Wigner Single reference Brillouin-Wigner expansions Single reference configuration Single reference configuration interaction Single reference configuration interaction expansions Single reference electronic structure Single reference many-body perturbation Single reference model spaces Single reference restricted coupled cluster theory Single reference unrestricted coupled cluster theory Single reference version Single-beam signal reference Single-determinant reference Single-reference CC theory Single-reference MMCC formalism Single-reference canonical transformation theory Single-reference cluster amplitudes Single-reference coupled cluster Single-reference coupled cluster approach Single-reference coupled cluster formalism Single-reference coupled cluster framework Single-reference coupled-cluster theory Single-reference function perturbation Single-reference many-body perturbation theory Single-reference methods Single-reference methods Hartree-Fock starting point Single-reference methods assessment Single-reference methods interactions approach Single-reference methods problem Single-reference methods substitutions method Single-reference methods theory Single-reference methods time-dependent density functional Single-reference perturbative methods Single-reference techniques, transition Single-reference theory, relationship Single-root formulation of multi-reference Brillouin-Wigner perturbation theory Single-root formulation of the multi-reference Brillouin-Wigner coupled-cluster theory Single-root multi-reference Brillouin-Wigner coupled cluster theory Hilbert space approach