FLEIM: A stable, accurate and robust extrapolation method at infinity for computing the ground state of electronic Hamiltonians

Étienne Polack; Yvon Maday; Andreas Savin

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arXiv · 2112.13139

FLEIM: A stable, accurate and robust extrapolation method at infinity for computing the ground state of electronic Hamiltonians

Étienne Polack·Yvon Maday·Andreas Savin

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Abstract

The Kohn-Sham method uses a single model system, and corrects it by a density functional the exact user friendly expression of which is not known and is replaced by an approximated, usable, model. We propose to use instead more than one model system, and use a greedy extrapolation method to correct the results of the model systems. Evidently, there is a higher price to pay for it. However, there are also gains: within the same paradigm, e.g., excited states and physical properties can be obtained.

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Étienne Polack, Yvon Maday, Andreas Savin. 2021-12-24. FLEIM: A stable, accurate and robust extrapolation method at infinity for computing the ground state of electronic Hamiltonians. https://arxiv.org/abs/2112.13139

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