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On the pairing of the natural orbitals for projected broken symmetry states


A pairing scheme for the natural orbitals of projected broken symmetry states, which can be expressed as a superposition of two generally non-orthogonal Slater determinants, is presented. The results obtained here are generalizations of a pairing scheme representation of natural orbitals derived recently by Hendeković within the complex molecular orbital method. As a simple example the Kekulé structure of benzene is discussed.

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Dalgaard, E. On the pairing of the natural orbitals for projected broken symmetry states. Theoret. Chim. Acta 64, 181–186 (1983).

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Key words

  • Natural orbitals
  • Broken symmetry
  • Complex molecular orbital method