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Exact exchange-correlation potential for a time-dependent two electron system

Irene D'Amico·Giovanni Vignale
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Abstract

We obtain an exact solution of the time-dependent Schroedinger equation for a two-electron system confined to a plane by an isotropic parabolic potential whose curvature is periodically modulated in time. From this solution we compute the exact time-dependent exchange correlation potential v_xc which enters the Kohn-Sham equation of time-dependent density functional theory. Our exact result provides a benchmark against which various approximate forms for v_xc can be compared. Finally v_xc is separated in an adiabatic and a pure dynamical part and it is shown that, for the particular system studied, the dynamical part is negligible.

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Irene D'Amico, Giovanni Vignale. 1998-09-09. Exact exchange-correlation potential for a time-dependent two electron system. https://doi.org/10.1103/physrevb.59.7876

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