Theoretica chimica acta

, Volume 68, Issue 3, pp 231–245 | Cite as

Population analysis based on occupation numbers II. Relationship between shared electron numbers and bond energies and characterization of hypervalent contributions

  • Claus Ehrhardt
  • Reinhart Ahlrichs


The population analysis based on occupation numbers, originally proposed by Davidson, is briefly reviewed. A new way is proposed to determine modified AOs and to characterize hypervalent contributions. This is discussed in application to the molecules NSF, NSF3, SF6, OPCl, OPCl2, O2PCl, SO2, ClO 4 . It is the main objective of this work to investigate the connection between shared electron numbers σ — considered as a measure of covalent bond strength — and bond energies, σ is found to be a reliable measure of bond energies.

Key words

Population analysis Bond energies Hypervalency 


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  1. 1.
    Mulliken, R. S.: J. Chem. Phys. 23, 1833 (1955)Google Scholar
  2. 2.
    Davidson, E. R.: J. Chem. Phys. 46, 3320 (1967)Google Scholar
  3. 3.
    Heinzmann, R., Ahlrichs, R.; Theoret. Chim. Acta (Berl.) 42, 33 (1976)Google Scholar
  4. 4.
    Roby, K. R.: Molec. Phys. 27, 81 (1974)Google Scholar
  5. 5.
    Cruickshank, D. W. J., Avramides, E. J.: Phil. Trans. R. Soc. Lond. A304, 533 (1982)Google Scholar
  6. 6.
    Schnöckel, H., Schunck, S.: private communicationGoogle Scholar
  7. 7.
    Kutzelnigg, W.: Einführung in die Theoretische Chemie II. Verlag Chemie, Weinheim 1978Google Scholar
  8. 8.
    Pauling, L.: Nature of the Chemical Bond. Cornell University Press 1960Google Scholar
  9. 9.
    Kutzelnigg, W., Staemmler, V., Gelus, M.: Chem. Phys. Letters 13, 496 (1972)Google Scholar
  10. 10.
    Benson, S. W.: J. Chem. Educ. 42, 502 (1965)Google Scholar
  11. 11.
    Herzberg, G.: Molecular Spectra and Molecular Structure I. D. van Nostrand 1955Google Scholar
  12. 12.
    Hanna, M.: Quantum Mechanics in Chemistry. Benjamin 1969Google Scholar

Copyright information

© Springer-Verlag 1985

Authors and Affiliations

  • Claus Ehrhardt
    • 1
  • Reinhart Ahlrichs
    • 1
  1. 1.Institut für Physikalische Chemie u. Elektrochemie, Lehrstuhl für Theoretische ChemieUniversitÄt KarlsruheKarlsruheFederal Republic of Germany

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