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

TL;DR

The paper introduces FLEIM, a novel extrapolation method at infinity for accurately computing the ground state of electronic Hamiltonians, enabling improved results by using multiple model systems and a greedy correction approach.

Contribution

It proposes a new extrapolation technique that leverages multiple models and greedy algorithms to enhance the accuracy and robustness of electronic structure calculations.

Findings

FLEIM achieves stable and accurate ground state computations.

The method allows for the calculation of excited states and physical properties.

Demonstrates improved robustness over traditional single-model approaches.

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.