Towards a formal definition of static and dynamic electronic correlations.

  title={Towards a formal definition of static and dynamic electronic correlations.},
  author={Carlos L Benavides-Riveros and Nektarios N. Lathiotakis and Miguel A. L. Marques},
  journal={Physical chemistry chemical physics : PCCP},
  volume={19 20},
Some of the most spectacular failures of density-functional and Hartree-Fock theories are related to an incorrect description of the so-called static electron correlation. Motivated by recent progress in the N-representability problem of the one-body density matrix for pure states, we propose a method to quantify the static contribution to the electronic correlation. By studying several molecular systems we show that our proposal correlates well with our intuition of static and dynamic electron… 

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