Approximating the Shifted Hartree-Exchange-Correlation Potential in Direct Energy Kohn–Sham Theory

Sharpe, Daniel J.; Levy, Mel; Tozer, David J.

Abstract

Levy and Zahariev [Phys. Rev. Lett. 113 113002 (2014)] have proposed a new approach for performing density functional theory calculations, termed direct energy Kohn–Sham (DEKS) theory. In this approach, the electronic energy equals the sum of orbital energies, obtained from Kohn–Sham-like orbital equations involving a shifted Hartree-exchange-correlation potential, which must be approximated. In the present study, density scaling homogeneity considerations are used to facilitate DEKS calculations on a series of atoms and molecules, leading to three nonlocal approximations to the shifted potential. The first two rely on preliminary Kohn–Sham calculations using a standard generalized gradient approximation (GGA) exchange-correlation functional and the results illustrate the benefit of describing the dominant Hartree component of the shift exactly. A uniform electron gas analysis is used to eliminate the need for these preliminary Kohn–Sham calculations, leading to a potential with an unconventional form that yields encouraging results, providing strong motivation for further research in DEKS theory.

Citation

Sharpe, D. J., Levy, M., & Tozer, D. J. (2018). Approximating the Shifted Hartree-Exchange-Correlation Potential in Direct Energy Kohn–Sham Theory. Journal of Chemical Theory and Computation, 14(2), 684-692. https://doi.org/10.1021/acs.jctc.7b01060

• Journal Article Type: Article
• Acceptance Date: Jan 3, 2018
• Online Publication Date: Jan 3, 2018
• Publication Date: Mar 1, 2018
• Deposit Date: Jan 24, 2018
• Publicly Available Date: Jan 3, 2019
• Journal: Journal of Chemical Theory and Computation
• Print ISSN: 1549-9618
• Electronic ISSN: 1549-9626
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 14
• Issue: 2
• Pages: 684-692
• DOI: https://doi.org/10.1021/acs.jctc.7b01060
• Public URL: https://durham-repository.worktribe.com/output/1340369