Oscillator Strengths from Time-dependent Density Functional Theory
نویسنده
چکیده
OF THE THESIS OSCILLATOR STRENGTHS FROM TIME-DEPENDENT DENSITY FUNCTIONAL THEORY by Heiko Appel Thesis Director: Kieron Burke We consider different forms of single-pole approximations (SPA) for oscillator-strengths in the response formalism of time-dependent density functional theory. Numerical calculations of oscillator strengths are presented for a simple model system, Hooke’s atom, and various ions of the Helium isoelectronic series with charges Z=2,4,10,20,80. Starting with the Kohn-Sham Hamiltonian as an unperturbed system the oscillator strengths are treated in first order Görling-Levy perturbation theory. It is then proven that the first order correction for the oscillator strengths vanishes for harmonic external potentials.
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