The seniority quantum number in Tensor Network States

  title={The seniority quantum number in Tensor Network States},
  author={Klaas Gunst and Dimitri Van Neck and Peter A. Limacher and Stijn De Baerdemacker},
  journal={arXiv: Chemical Physics},
We employ tensor network methods for the study of the seniority quantum number - defined as the number of unpaired electrons in a many-body wave function - in molecular systems. Seniority-zero methods recently emerged as promising candidates to treat strong static correlations in molecular systems, but are prone to deficiencies related to dynamical correlation and dispersion. We systematically resolve these deficiencies by increasing the allowed seniority number using tensor network methods. In… 
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