On the relation between the scalar and tensor exchange-correlation kernels of the time-dependent density-functional theory

V. U. Nazarov; G. Vignale; Y. -C. Chang

doi:10.1063/1.3455711

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arXiv · 1001.2795

On the relation between the scalar and tensor exchange-correlation kernels of the time-dependent density-functional theory

V. U. Nazarov·G. Vignale·Y. -C. Chang

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Abstract

The scalar $f_{xc}$ and tensor $\hat{f}_{xc}$ exchange-correlation (xc) kernels are key ingredients of the time-dependent density functional theory and the time-dependent current density functional theory, respectively. We derive a comparatively simple relation between these two kernels under the assumption that the dynamic xc can be considered "weak". We expect our formula to serve as a convenient bridge between the scalar $f_{xc}$ which directly enters many applications and the tensor $\hat{f}_{xc}$ which, due to its locality in space, is much easier to approximate.

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V. U. Nazarov, G. Vignale, Y. -C. Chang. 2010-01-16. On the relation between the scalar and tensor exchange-correlation kernels of the time-dependent density-functional theory. https://doi.org/10.1063/1.3455711

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