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arXiv · 1409.6435

Why doubly excited determinants govern configuration interaction calculations of electron correlations

Carlos L. Benavides-Riveros·José M. Gracia-Bondía·Michael Springborg
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Abstract

Computational evidence shows that, when using natural orbitals to study (dynamical and non-dynamical) electron correlation, determinants with an odd number of excitations play a negligible role. Instead, doubly excited determinants rule the rostrum in this kind of configuration interaction calculations. We explain mathematically why it must be so.

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Carlos L. Benavides-Riveros, José M. Gracia-Bondía, Michael Springborg. 2014-09-23. Why doubly excited determinants govern configuration interaction calculations of electron correlations. https://arxiv.org/abs/1409.6435

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