Constrained-Pairing Mean-Field Theory. IV. Inclusion of corresponding pair constraints and connection to unrestricted Hartree-Fock theory

摘要

Our previously developed Constrained-Pairing Mean-Field Theory (CPMFT) isshown to map onto an Unrestricted Hartree-Fock (UHF) type method if one imposesa corresponding pair constraint to the correlation problem that forcesoccupation numbers to occur in pairs adding to 1. In this new version, CPMFThas all the advantages of standard independent particle models (orbitals andorbital energies, to mention a few), yet unlike UHF, it can dissociatepolyatomic molecules to the correct ground-state restricted open-shellHartree-Fock atoms or fragments.