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arXiv · 1911.06767

Exact non-adiabatic part of the Kohn-Sham potential and its fluidic approximation

Mike Entwistle·Rex Godby
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Abstract

We present a simple geometrical "fluidic" approximation to the non-adiabatic part of the Kohn-Sham potential, $v_{\mathrm{KS}}$, of time-dependent density functional theory. This part of $v_{\mathrm{KS}}$ is often crucial, but most practical functional approximations utilize an adiabatic approach based on ground-state DFT. For a variety of prototype systems, we calculate the exact time-dependent electron density, and find that the fluidic approximation corrects a large part of the error arising from the "exact adiabatic" approach, even when the system is evolving far from adiabatically.

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Mike Entwistle, Rex Godby. 2019-11-15. Exact non-adiabatic part of the Kohn-Sham potential and its fluidic approximation. https://doi.org/10.1103/physrevmaterials.4.035002

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