Excitation energies from ground-state density-functionals by means of generator coordinates

E. Orestes; A. B. F. da Silva; K. Capelle

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arXiv · 0712.1586

Excitation energies from ground-state density-functionals by means of generator coordinates

E. Orestes·A. B. F. da Silva·K. Capelle

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Abstract

The generator-coordinate method is a flexible and powerful reformulation of the variational principle. Here we show that by introducing a generator coordinate in the Kohn-Sham equation of density-functional theory, excitation energies can be obtained from ground-state density functionals. As a viability test, the method is applied to ground-state energies and various types of excited-state energies of atoms and ions from the He and the Li isoelectronic series. Results are compared to a variety of alternative DFT-based approaches to excited states, in particular time-dependent density-functional theory with exact and approximate potentials.

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E. Orestes, A. B. F. da Silva, K. Capelle. 2009-04-24. Excitation energies from ground-state density-functionals by means of generator coordinates. https://arxiv.org/abs/0712.1586

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