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Excitations in time-dependent density-functional theory

H. Appel·E. K. U. Gross·K. Burke
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Abstract

An approximate solution to the time-dependent density functional theory (TDDFT) response equations for finite systems is developed, yielding corrections to the single-pole approximation. These explain why allowed Kohn-Sham transition frequencies and oscillator strengths are usually good approximations to the true values, and why sometimes they are not. The approximation yields simple expressions for Görling-Levy perturbation theory results, and a method for estimating expectation values of the unknown exchange-correlation kernel.

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H. Appel, E. K. U. Gross, K. Burke. 2002-03-01. Excitations in time-dependent density-functional theory. https://doi.org/10.1103/physrevlett.90.043005

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