Institute Seminar | Andreas Görling | 2021.02.23 | 2/2 Discussion
Channel: CASUS.science
Date: 23/11/2021

TITLE: Electron correlation via the adiabatic-connection dissipation- fluctuation theorem and temperature-dependent exact exchange by Andreas Görling, Friedrich-Alexander University Erlangen-Nürnberg

ABSTRACT:
Electronic structure methods using orbital-dependent exchange-correlation functionals within the Kohn-Sham (KS) formalism of density-functional theory are introduced. An approach to treat the KS exchange energy and potential exactly in the case of non-zero temperature is presented and applied to describe topological phase transitions in zinc-blende compounds [1,2]. The treatment of electron correlation based on the adiabatic-connection fluctuation-dissipation theorem is discussed [3,4] and a new class of correlation functionals, named sigma-functionals, is presented [5]. Technically, sigma-functionals are very similar to functionals within the well-known random phase approximation and have similar computational demands. The accuracy of sigma-functionals, however, is substantially higher than that of functionals within the random-phase approximation. Indeed, reaction and transition state energies of molecules from various established test sets as well as Van-der-Waals binding energies from sigma-functionals are as accurate as those from high level quantum quemistry methods [5] that are computationally much more demanding and therefore quite limitied in their range of application. Sigma-functionals therefore open up new areas of application for KS methods in chemistry, physics, and materials science.

1. M. Greiner, P. Carrier, and A. Gorling, Phys. Rev. B 81, 155119 (2010).
2. E. Trushin and A. Gorling, Phys. Rev. Lett. 120, 146401 (2018).
3. J. Erhard, P. Bleizier, and A. Gorling, Phys. Rev. Lett. 117, 143002 (2016).
4. A. Gorling, Phys. Rev. B 99, 235120 (2019).
5. E. Trushin, A. Thierbach, A. Gorling, J. Chem. Phys. 154, 014104 (2021).

LICENSE:
CC BY-SA 4.0

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