Stability of the complex generalized Hartree-Fock equations

Journal Article · Tue Apr 21 04:00:00 EDT 2015 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4918561· OSTI ID:22415660

Goings, Joshua J.; Ding, Feizhi; Li, Xiaosong ^[1]; Frisch, Michael J. ^[2]

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1. Department of Chemistry, University of Washington, Seattle, Washington 98195 (United States)
2. Gaussian, Inc., 340 Quinnipiac St., Bldg 40, Wallingford, Connecticut 06492 (United States)

For molecules with complex and competing magnetic interactions, it is often the case that the lowest energy Hartree-Fock solution may only be obtained by removing the spin and time-reversal symmetry constraints of the exact non-relativistic Hamiltonian. To do so results in the complex generalized Hartree-Fock (GHF) method. However, with the loss of variational constraints comes the greater possibility of converging to higher energy minima. Here, we report the implementation of stability test of the complex GHF equations, along with an orbital update scheme should an instability be found. We apply the methodology to finding the local minima of several spin-frustrated hydrogen rings, as well as the non-collinear molecular magnet Cr{sub 3}, illustrating the utility of the broken symmetry GHF method and some of its lesser-known nuances.

• OSTI ID: 22415660
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 15 Vol. 142; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ELECTRIC UTILITIES
HAMILTONIANS
HARTREE-FOCK METHOD
HYDROGEN
MAGNETISM
MATHEMATICAL SOLUTIONS
MOLECULES
SPIN
SYMMETRY BREAKING
VARIATIONAL METHODS