Density functional theory with fractional orbital occupations.

  title={Density functional theory with fractional orbital occupations.},
  author={Jeng-Da Chai},
  journal={The Journal of chemical physics},
  volume={136 15},
  • Jeng-Da Chai
  • Published 23 January 2012
  • Chemistry
  • The Journal of chemical physics
In contrast to the original Kohn-Sham (KS) formalism, we propose a density functional theory (DFT) with fractional orbital occupations for the study of ground states of many-electron systems, wherein strong static correlation is shown to be described. Even at the simplest level represented by the local density approximation (LDA), our resulting DFT-LDA is shown to improve upon KS-LDA for multi-reference systems, such as dissociation of H(2) and N(2), and twisted ethylene, while performing… 

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