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Spin-projected generalized Hartree-Fock method as a polynomial of particle-hole excitations

Journal Article · · Physical Review A
 [1];  [2]
  1. Rice Univ., Houston, TX (United States); DOE/OSTI
  2. Rice Univ., Houston, TX (United States)
The past several years have seen renewed interest in the use of symmetry-projected Hartree-Fock for the description of strong correlations. Unfortunately, these symmetry-projected mean-field methods do not adequately account for dynamic correlation. Presumably, this shortcoming could be addressed if one could combine symmetry-projected Hartree-Fock with a many-body method such as coupled-cluster theory, but this is by no means straightforward because the two techniques are formulated in very different ways. However, we have recently shown that the singlet S2-projected unrestricted Hartree-Fock wave function can in fact be written in a coupled-cluster-like wave function. That is, the spin-projected unrestricted Hartree-Fock wave function can be written as a polynomial of a double-excitation operator acting on some closed-shell reference determinant. Here, we extend this result and show that the spin-projected generalized Hartree-Fock wave function (which has both S2 and Sz projection) is likewise a polynomial of low-order excitation operators acting on a closed-shell determinant and provide a closed-form expression for the resulting polynomial coefficients. The spin projection of the generalized Hartree-Fock wave function introduces connected triple and quadruple excitations which are absent when spin-projecting an unrestricted Hartree-Fock determinant. We include a few preliminary applications of the combination of this spin-projected Hartree-Fock and coupled-cluster theory to the Hubbard Hamiltonian and comment on generalizations of the methodology. Results here are not for production level, but a similarity-transformed theory that combines the two offers the promise of being accurate for both weak and strong correlation, and may offer significant improvements in the intermediate correlation regime where neither projected Hartree-Fock nor coupled cluster is particularly accurate.
Research Organization:
Rice Univ., Houston, TX (United States)
Sponsoring Organization:
USDOE; USDOE Office of Science (SC)
Grant/Contract Number:
SC0001474
OSTI ID:
1535748
Alternate ID(s):
OSTI ID: 1374068
Journal Information:
Physical Review A, Journal Name: Physical Review A Journal Issue: 2 Vol. 96; ISSN 2469-9926
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

References (33)

On the solution of coupled-cluster equations in the fully correlated limit of cyclic polyene model journal January 1991
Electron correlation in one dimension: Coupled cluster approaches to cyclic polyene ?-electron models journal April 1992
The expectation value coupled-cluster method and analytical energy derivatives journal September 1988
Stability conditions and nuclear rotations in the Hartree-Fock theory journal November 1960
Comparison between exact and approximate treatments of the pairing interaction for finite Fermi systems journal February 2003
On the use of general symmetry-projected Hartree–Fock–Bogoliubov configurations in variational approaches to the nuclear many-body problem journal April 2004
Black-Box Description of Electron Correlation with the Spin-Extended Configuration Interaction Model: Implementation and Assessment journal March 2016
Generalized Hartree–Fock Description of Molecular Dissociation
  • Jiménez-Hoyos, Carlos A.; Henderson, Thomas M.; Scuseria, Gustavo E.
  • Journal of Chemical Theory and Computation, Vol. 7, Issue 9 https://doi.org/10.1021/ct200345a
journal July 2011
Entanglement and Polyradical Character of Polycyclic Aromatic Hydrocarbons Predicted by Projected Hartree–Fock Theory journal May 2013
Predicting Singlet–Triplet Energy Splittings with Projected Hartree–Fock Methods journal July 2013
Stability of Hemi-Bonded vs Proton-Transferred Structures of (H 2 O) 2 + , (H 2 S) 2 + , and (H 2 Se) 2 + Studied with Projected Hartree–Fock Methods journal January 2014
Polyradical Character and Spin Frustration in Fullerene Molecules: An Ab Initio Non-Collinear Hartree–Fock Study journal October 2014
Benchmark variational coupled cluster doubles results journal November 2000
Benchmark studies of variational, unitary and extended coupled cluster methods journal December 2010
Alternative single-reference coupled cluster approaches for multireference problems: The simpler, the better journal June 2011
Projected Hartree–Fock theory journal April 2012
Excited electronic states from a variational approach based on symmetry-projected Hartree–Fock configurations journal December 2013
Extended Møller-Plesset perturbation theory for dynamical and static correlations journal October 2014
Communication: Configuration interaction combined with spin-projection for strongly correlated molecular electronic structures journal January 2016
Communication: Projected Hartree Fock theory as a polynomial similarity transformation theory of single excitations journal September 2016
Merging symmetry projection methods with coupled cluster theory: Lessons from the Lipkin model Hamiltonian journal February 2017
Projected Hartree-Fock theory as a polynomial of particle-hole excitations and its combination with variational coupled cluster theory journal May 2017
Attenuated coupled cluster: a heuristic polynomial similarity transformation incorporating spin symmetry projection into traditional coupled cluster theory journal January 2017
Symmetry broken and restored coupled-cluster theory: I. Rotational symmetry and angular momentum journal December 2014
Symmetry broken and restored coupled-cluster theory: II. Global gauge symmetry and particle number journal December 2016
Erratum: Symmetry broken and restored coupled-cluster theory: II. Global gauge symmetry and particle number (2017 J. Phys. G: Nucl. Part. Phys. 44 015103) journal February 2017
Electron correlations in narrow energy bands journal November 1963
Quantum Theory of Many-Particle Systems. III. Extension of the Hartree-Fock Scheme to Include Degenerate Systems and Correlation Effects journal March 1955
Approximate account of connected quadruply excited clusters in single-reference coupled-cluster theory via cluster analysis of the projected unrestricted Hartree-Fock wave function journal August 1996
Coupled-cluster approaches with an approximate account of triexcitations and the optimized-inner-projection technique. II. Coupled-cluster results for cyclic-polyene model systems journal August 1990
Variational description of the ground state of the repulsive two-dimensional Hubbard model in terms of nonorthogonal symmetry-projected Slater determinants journal November 2014
Polynomial similarity transformation theory: A smooth interpolation between coupled cluster doubles and projected BCS applied to the reduced BCS Hamiltonian journal March 2016
Combining symmetry collective states with coupled-cluster theory: Lessons from the Agassi model Hamiltonian journal June 2017

Cited By (6)

Projected coupled cluster theory journal August 2017
Open-shell coupled-cluster valence-bond theory augmented with an independent amplitude approximation for three-pair correlations: Application to a model oxygen-evolving complex and single molecular magnet journal December 2018
Projected coupled cluster theory: Optimization of cluster amplitudes in the presence of symmetry projection journal October 2018
Polynomial-product states: A symmetry-projection-based factorization of the full coupled cluster wavefunction in terms of polynomials of double excitations journal April 2019
Unrestricted treatment for the direct variational determination of the two-electron reduced density matrix for doubly occupied-configuration-interaction wave functions journal April 2019
Open-Shell Coupled-Cluster Valence-Bond Theory Augmented with an Independent Amplitude Approximation for Three-Pair Correlations: Application to a Model Oxygen-Evolving Complex and Single Molecular Magnet text January 2018

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