Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2012-02-14
J. Chem. Phys. 136, 164109 (2012)
Physics
Condensed Matter
Strongly Correlated Electrons
Scientific paper
10.1063/1.4705280
Projected Hartree-Fock theory (PHF) has a long history in quantum chemistry. PHF is here understood as the variational determination of an N-electron broken symmetry Slater determinant that minimizes the energy of a projected state with the correct quantum numbers. The method was actively pursued for several decades but seems to have been abandoned. We here derive and implement a "variation after projection" PHF theory using techniques different from those previously employed in quantum chemistry. Our PHF methodology has modest mean-field computational cost, yields relatively simple expressions, can be applied to both collinear and non-collinear spin cases, and can be used in conjunction with deliberate symmetry breaking and restoration of other molecular symmetries like complex conjugation and point group. We present several benchmark applications to dissociation curves and singlet-triplet energy splittings, showing that the resulting PHF wavefunctions are of high quality multireference character. We also provide numerical evidence that in the thermodynamic limit, the energy in PHF is not lower than that of broken-symmetry HF, a simple consequence of the lack of size consistency and extensivity of PHF.
Henderson Thomas M.
Jimenez-Hoyos Carlos A.
Scuseria Gustavo E.
Tsuchimochi Takashi
No associations
LandOfFree
Projected Hartree-Fock Theory does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Projected Hartree-Fock Theory, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Projected Hartree-Fock Theory will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-555932