Theoretica chimica acta

, Volume 25, Issue 2, pp 181–188 | Cite as

Integral Hellmann-Feynman investigations oftrans bent acetylene

  • M. P. Melrose
  • P. J. Briggs


The integral Hellmann-Feynman (IHF) theorem has been applied to various wavefunctions representing the1A u state of acetylene with a view to testing traditional explanations of the excited state geometry. When LCAOSCF wavefunctions are used, the electronic energy changes associated with the individual corresponding orbitals (CMG's) are in sympathy with the trend in orbital (i.e. MO) energies suggested by Walsh. However, when LMO wavefunctions based on hybrid AO's are employed, the IHF results are against all experience; and imply that a change in hybridisation, fromsp tosp2, is not a viable model for the change in geometry.


Physical Chemistry Inorganic Chemistry Organic Chemistry Excited State Acetylene 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Ingold, C. K., King, G. W.: J. chem. Soc.1953, 2702.Google Scholar
  2. 2.
    Walsh, A. D.: J. chem. Soc.1953, 2288.Google Scholar
  3. 3.
    See for example, Murrell, J. N., Kettle, S. F. A., Tedder, J. M.: Valence theory, p. 192. John Wiley: 1965.Google Scholar
  4. 4.
    Burnelle, L.: J. chem. Physics35, 311 (1961).Google Scholar
  5. 5.
    Kammer, W. E.: Chem. Physics Letters6, 529 (1970).Google Scholar
  6. 6.
    Peyerimhoff, S. D., Buenker, R. J., Allen, L. C.: J. chem. Physics45, 734 (1966).Google Scholar
  7. 7.
    Pan, D. C., Allen, L. C.: J. chem. Physics46, 1797 (1966).Google Scholar
  8. 8.
    Whitten, J. L.: J. chem. Physics44, 359 (1966).Google Scholar
  9. 9.
    Parr, R. G.: J. chem. Physics40, 3726 (1964).Google Scholar
  10. 10.
    , Wyatt, R. E.: J. chem. Physics44, 1529 (1966).Google Scholar
  11. 11.
    Melrose, M. P., Parr, R. G.: Theoret. chim. Acta (Berl.)8, 150 (1967).Google Scholar
  12. 12.
    Fink, W. H., Allen, L. C.: J. chem. Physics46, 3270 (1967).Google Scholar
  13. 13.
    Rothstein, S. M., Blinder, S. M.: Theoret. chim. Acta (Berl.)8, 427 (1967).Google Scholar
  14. 14.
    Marron, M. T.: J. chem. Physics52, 3600 (1970).Google Scholar
  15. 15.
    McLean, A. D., Ransil, B. J., Mulliken, R. S.: J. chem. Physics32, 1873 (1960).Google Scholar
  16. 16.
    Woznicki, W.: Bull. Acad. Polon. Sci., Ser. Sci. Math., Astr. et Phys.9, 273 (1961).Google Scholar
  17. 17.
    Newton, M. D., Switkes, E., Lipscomb, W. N.: J. chem. Physics53, 2645 (1970).Google Scholar
  18. 18.
    Switkes, E., Stevens, R. M., Lipscomb, W. N.: J. chem. Physics51, 5229 (1969).Google Scholar

Copyright information

© Springer-Verlag 1972

Authors and Affiliations

  • M. P. Melrose
    • 1
  • P. J. Briggs
    • 1
  1. 1.Department of ChemistryKing's CollegeLondonEngland

Personalised recommendations