Theoretica chimica acta

, Volume 63, Issue 6, pp 497–509 | Cite as

Valency. I. A quantum chemical definition and properties

  • M. S. Gopinathan
  • Karl Jug
Original Investigations


A quantum chemical definition of the valency of an atom in a molecule is proposed. It is defined as the sum of the squares of the appropriate offdiagonal elements of the first-order density matrix of the system in an orthogonal basis. It is a measure of the degree of electron sharing of the given atom with the other atoms. Its properties such as invariance to rotation of the coordinate system, its limiting values as well as its relation to natural hybrids and bond orbitals are discussed.

Key words

Definition and properties of valency 


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Copyright information

© Springer-Verlag 1983

Authors and Affiliations

  • M. S. Gopinathan
    • 1
  • Karl Jug
    • 1
  1. 1.Theoretische ChemieUniversität HannoverHannoverFederal Republic of Germany

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