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Theoretica chimica acta

, Volume 10, Issue 3, pp 269–284 | Cite as

Non-empirical LCAO-MO-SCF-CI calculations on organic molecules with Gaussian type functions

IV. Preliminary investigations on formamide
  • M. A. Robb
  • I. G. Csizmadia
Commentationes

Abstract

Single detor wavefunctions were calculated for formamide (HCONH2) in the LCAO-MO-SCF framework using a basis of Gaussian type functions (GTF) centered on the individual atoms. Preliminary calculations were carried out on various planar and non-planar configurations of the amide hydrogens. A planar model was found to be the most stable and this planar species was used as the model for the investigation of physical properties. Ground state molecular properties investigated for formamide include ionization potentials, dipole moment, electron populations and one electron and total electron densities. Low lying excited state energies were calculated accurately using a single co-detor wavefunction and the predicted electronic transitions were associated with the previously reported experimental UV spectrum.

Keywords

Formamide Planar Model Total Electron HCONH2 Preliminary Calculation 
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.

Zusammenfassung

Der Grundzustand von Formamid (HCONH2) wurde mittels der LCAO-MO-SCF-Methode mit einem GTF Basissatz berechnet. Dabei ergab sich, da\ das planare Molekül am stabilsten ist; für diese Konfiguration wurden Ionisationspotential, Dipolmoment, Elektronen-Population, Ein- und Gesamtelektronendichte berechnet. Die untersten angeregten ZustÄnde wurden mit einem einfachen Co-Detor berechnet und die ElektronenübergÄnge mit dem experimentellen UV-Spektrum verglichen.

Résumé

On a calculé des fonctions d'onde simples déterminants pour la formamide (HCONH2) dans le cadre de la méthode LCAO-MO-SCF en utilisant une base de fonctions du type gaussien (GTF) centrées sur les différents atomes. Des calculs préliminaires ont été effectués pour diverses configurations planes et non planes des atomes d'hydrogène du groupement amide. Un modèle plan s'est avéré le plus stable; il a été utilisé pour l'étude des propriétés physiques. Les propriétés moléculaires de l'état fondamental étudiées sont: les potentiels d'ionisation, le moment dipolaire, les populations électroniques et les densités électroniques. Les énergies des états excités inférieure ont été calculées avec précision en utilisant une simple combinaison de déterminants; les transitions électroniques ainsi prédites sont mises en correspondance avec le spectre U.V. expérimental publié auparavant.

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References

  1. 1.
    Basch, H., M. B. Robin, and N. A. Kuebler: J. chem. Physics 47, 1201 (1967).Google Scholar
  2. 2.
    Body, R. G., and E. Clementi (to be published): Presented at 1967 “March” Meeting of the APS (Chicago; March 27–30, 1967).Google Scholar
  3. 3.
    Clementi, E.: San Jose Research Note MJ-7 (1962).Google Scholar
  4. 4.
    Costain, C. C., and J. M. Dowling: J. chem. Physics 32, 158 (1960).Google Scholar
  5. 5.
    Cotterell, F. C.: Strength of Chemical Bonds. London: Butterworths 1965.Google Scholar
  6. 6.
    Csizmadia, I. G., M. C. Harrison, J. W. Moskowitz, S. S. Seung, B. T. Sutcliffe, and M. P. Barnett: The POLYATOM System, Technical Notes Nos. 36 and 40, Co-operative Computing Laboratory, M.I.T. (unpublished). Submitted to the Quantum Chemistry Program Exchange, Catalogue No. 47 A.Google Scholar
  7. 7.
    — —, and B. T. Sutcliffe: Quaterly Progress Report (MIT-SSMTG) 50, 4 (1963).Google Scholar
  8. 8.
    — —, J. W. Moskowitz, and B. T. Sutcliffe: Theoret. chim. Acta (Berl.) 6, 191 (1966).Google Scholar
  9. 9.
    — —, and B. T. Sutcliffe: Theoret. chim. Acta (Berl.) 6, 217 (1966).Google Scholar
  10. 10.
    -Quantum Chemistry Program Exchange (QCPE) Newsletter 12 (January 1966).Google Scholar
  11. 11.
    Evans, J. C.: J. chem. Physics 22, 1228 (1954).Google Scholar
  12. 12.
    Gaydon, A. G.: Dissociation Energies of Diatomic Molecules. London: 2nd Ed., Chapman and Hall Ltd. 1953.Google Scholar
  13. 13.
    Hunt, H. D., and W. T. Simpson: J. Amer. chem. Soc. 75, 4540 (1953).Google Scholar
  14. 14.
    Herzberg, G.: Spectra of Diatomic Molecules. Toronto: D. Van Nostrand 1955.Google Scholar
  15. 15.
    —: Electronic Spectra and Electronic Structure of Polyatomic Molecules. Toronto: D. Van Nostrand 1966.Google Scholar
  16. 16.
    Huzinaga, S.: J. chem. Physics 42, 1293 (1965).Google Scholar
  17. 17.
    Julug, A.: Theoret. chim. Acta (Berl.) 1, 140 (1963).Google Scholar
  18. 18.
    —: Theoret. chim. Acta (Berl.) 7, 103 (1967).Google Scholar
  19. 19.
    Kahan, W., and D. Corneil: University of Toronto, Institute of Computer Science, Programmers Reference Manual and D. Corneil, M. Sc. Thesis, University of Toronto (1966).Google Scholar
  20. 20.
    Kari, R. E., and I. G. Csizmadia (to be published): Presented at the “Second Canadian Symposium on Quantum Chemistry” (Montreal, June 26–30, 1967).Google Scholar
  21. 21.
    Kromhout, R. A., and G. W. Moulton: J. chem. Physics 25, 35 (1956).Google Scholar
  22. 22.
    Kurland, R. J., and E. B. Wilson: J. chem. Physics 27, 585 (1957).Google Scholar
  23. 23.
    Mulliken, R. S.: J. chem. Physics 23, 1833 (1955).Google Scholar
  24. 24.
    Nagakura, S.: Molecular Physics 3, 105 (1960).Google Scholar
  25. 25.
    —: Theoret. chim. Acta (Berl.) 7, 117 (1967).Google Scholar
  26. 26.
    Peterson, D. L., and W. T. Simpson: J. Amer. chem. Soc. 79, 2375 (1957).Google Scholar
  27. 27.
    Post, C., and J. Ladell: Acta Cryst. 7, 559 (1954).Google Scholar
  28. 28.
    Reeves, C. M.: J. chem. Physics 39, 1 (1963).Google Scholar
  29. 29.
    Robb, M. A., and I. G. Csizmadia: “Non-Empirical MO Calculations on Formamide”, 50th National Conference of the Chemical Institute of Canada, Toronto, June 4–7, 1967. (Deadline of submitting Abstracts was set to be February 1, 1967. The programme of the Conference has been published in “Chemistry in Canada” 19, 37 (April, 1967) and the paper was presented at June 5, 1967.)Google Scholar
  30. 30.
    -Non-Empirical LCAO-MO-SCF Calculations on Formamide, Formaldoxime and Nitrone, M. Sc. Thesis, University of Toronto, September, 1967.Google Scholar
  31. 31.
    Roothaan, C. C. J.: Rev. mod. Physics 23, 69 (1951).Google Scholar
  32. 32.
    Ruedenberg, K.: Rev. mod. Physics 34, 326 (1962).Google Scholar
  33. 33.
    Suard-Sender, M.: J. Chim. physique 62, 79 (1965).Google Scholar
  34. 34.
    Tanaka, J.: Nippon Kagaka Zasshi 78, 1636 (1957).Google Scholar

Copyright information

© Springer-Verlag 1968

Authors and Affiliations

  • M. A. Robb
    • 1
  • I. G. Csizmadia
    • 1
  1. 1.Lash Miller Chemical Laboratories, Department of ChemistryUniversity of TorontoUSA

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