Response Potential in the Strong-Interaction Limit of Density Functional Theory: Analysis and Comparison with the Coupling-Constant Average

Sara Giarrusso; Stefan Vuckovic; Paola Gori-Giorgi

doi:10.1021/acs.jctc.8b00386

Response Potential in the Strong-Interaction Limit of Density Functional Theory: Analysis and Comparison with the Coupling-Constant Average

J Chem Theory Comput. 2018 Aug 14;14(8):4151-4167. doi: 10.1021/acs.jctc.8b00386. Epub 2018 Jul 5.

Authors

Sara Giarrusso¹, Stefan Vuckovic¹, Paola Gori-Giorgi¹

Affiliation

¹ Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling, FEW , Vrije Universiteit , De Boelelaan 1083 , 1081HV Amsterdam , The Netherlands.

Abstract

Using the formalism of the conditional amplitude, we study the response part of the exchange-correlation potential in the strong-coupling limit of density functional theory, analyzing its peculiar features and comparing it with the response potential averaged over the coupling constant for small atoms and for the hydrogen molecule. We also use a simple one-dimensional model of a stretched heteronuclear molecule to derive exact properties of the response potential in the strong-coupling limit. The simplicity of the model allows us to unveil relevant features also of the exact Kohn-Sham potential and its different components, namely the appearance of a second peak in the correlation kinetic potential on the side of the most electronegative atom.