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The Molecular Orbital-Valence Bond Theory of Inorganic Chemistry

  • Nicolaos Demetrios Epiotis
Part of the Lecture Notes in Chemistry book series (LNC, volume 34)

Abstract

The purpose of this paper is to rephrase the fundamental concepts of inorganic chemistry in the language of MOVB theory1 as a prelude to a reexamination of the electronic structure of inorganic molecules. For illustrative purposes we reformulate the concepts of the coordinate bond,2 the Dewar-Chatt-Duncanson (DCD) model,3 and the concept of high and low spin complexes4 and we apply MOVB theory to the problem of the ground stereochemistry of prototypical inorganic complexes, the thermodynamics of olefin coordination in complexes, and the problem of the “trans effect” in the equilibrium geometries of inorganic complexes.5

Keywords

High Spin Coordinate Bond Coulomb Correlation Trans Effect Ligand Orbital 
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.

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References

  1. 1.
    Epiotis, N.D., Larson, J.R., Eaton, H., “Unified Valence Bond Theory of Electronic Structure” in Lecture Notes in Chemistry, Vol. 29; Springer-Verlag: New York and Berlin, 1982.Google Scholar
  2. 2.
    a) Basolo, F., Johnson, R.G., “Coordination Chemistry”; W. A. Bemjamin, Inc.: New York, 1964.Google Scholar
  3. (b).
    Cotton, F.A., Wilkinson, G., “Advanced Inorganic Chemistry”, 2nd Ed.; Interscience: New York, 1966.Google Scholar
  4. 4.
    Huheey, J.E., “Inorganic Chemistry”, 2nd Ed.; Harper and Row: New York, 1978.Google Scholar
  5. (a).
    Chernyaev, I.I. Ann. Inst. Platine (U.S.S.R.) 1929, 4, 243.Google Scholar
  6. (b).
    Venanzi, L.M., Chem. in Britain, 1968, 5, 162.Google Scholar
  7. 6.
    For important contributions to the theory of the electronic structure of transition metal complexes using the EHMO method see:Google Scholar
  8. a). Elian, M., Hoffmann, R., Inorg. Chem. 1975, 14, 1058 and subsequent papers of the Hoffmann school.Google Scholar
  9. (b).
    Burdett, J.K. Chem. Soc.-Rev. 1978, 7, 507.CrossRefGoogle Scholar
  10. 7.
    Methane, the prototypical molecules of organic chemistry,is the “result” of the “forbidden” union of C and H4.Google Scholar
  11. 8.
    In this analysis, we assume that an energy minimum due to coulomb correlation (van der Waal s attraction) is absent and that state A is purely repulsive.Google Scholar
  12. 9.
    This is due to the fact that the percentage of “ionic” CW’s, which involve strong interelectronic repulsion, decreases as the number of open shell electrons having the same spin increases. For explanations, see the chapter dealing with the electronic structure of excited states.Google Scholar
  13. 10. (a)
    Itel, S.D.; Ibers, J.A. Adv. Organomet. Chem. 1976, 14, 33.CrossRefGoogle Scholar
  14. (b).
    Nelson, J.H.; Jonassen, H.B. Coordination Chem. Rev. 1971, 6, 27.CrossRefGoogle Scholar
  15. (c).
    An extensive list of primary references can be found in: Albright, T.A.; Hoffmann, R.; Thibeault, J.C.; Thorn, D.L. J Am. Chem. Soc. 1979, 101, 3801.CrossRefGoogle Scholar
  16. 11. (a)
    Vaska, L. Accounts Chem. Res. 1976, 9, 175.CrossRefGoogle Scholar
  17. (b).
    Valentine, J.S., Chem. Rev. 1973, 73, 235.CrossRefGoogle Scholar
  18. (c).
    Choy, Y.J.; O’Connor, C.J. Coordination Chem. Rev. 1972, 9, 145.CrossRefGoogle Scholar
  19. 12.
    Black, M., Mais, R.H.B., Owston, P.G., Acta Cryst. 1969, B25, 1753.CrossRefGoogle Scholar
  20. 13.
    The pi C-C and strengths of CH2=CH2 and CF2=CF2 are discussed in:Google Scholar
  21. (a).
    Berrson, S.W. J Chem. Ed. 1965, 42, 502 (C2H4).CrossRefGoogle Scholar
  22. (b).
    Wu, E.C., Rodgers, A.S., J. Am. Chem. Soc. 1976, 98, 6112 (C2F4).Google Scholar
  23. 14.
    The lowest ionization potentials of CH2=CH2 and CF2=CF2 are almost identical. The electron affinity of CH2=CH2 is nearly the same as that of CF2=CFCℓ,, a close relative of CF2=CF2, as the vertical electron attachment energies differ by only 0.24 eV.Google Scholar
  24. Burrow, P.D., Modelli, A., Chiu, N.S., Jordan, K.D., Chem. Phys. Letters, in press. Hence, it is safe to assume that CH2=CH2 and CF2=CF2 do not differ significantly in either their pi donor or pi acceptor ability.Google Scholar
  25. 15.
    For experimental evidence in support of the generalization that many fluoroolefins form more stable complexes with metals than olefins with other substituents and that, in particular, C2F4 binds more strongly to metals than C2H4, see:Google Scholar
  26. (a).
    Cramer, R. J. Am. Chem. Soc. 1967, 89, 4621.CrossRefGoogle Scholar
  27. (b).
    Cramer, R., Kline, J.B., Roberts, J.D., J. Am. Chem. Soc. 1969, 91, 2519.Google Scholar
  28. (c).
    Fields, R., Germain, M.M., Haszeldine, R.N., Wiggins, P.W., J. Chem. Soc. A 1970, 1969.Google Scholar
  29. (d).
    Guggenberger, L.J., Cramer, R., J. Am. Chem. Soc. 1972, 94, 3779.CrossRefGoogle Scholar
  30. (e).
    Stone, F.G.A. Pure Appl. Chem. 1972, 30, 551.CrossRefGoogle Scholar
  31. 16.
    Vaska, L. Accounts Chem. Res. 1968, 1, 335.CrossRefGoogle Scholar
  32. 17.
    For example, see Chapter 6.Google Scholar
  33. 18.
    The trans isomer of square planar Pt(II)A2X2 complexes is favored by entropy and the cis by enthalpy: Chatt, J., Wilkins, R.G., J. Chem. Soc. 1952, 273, ibid. 1956, 525.Google Scholar
  34. 19.
    Pidcock, A., Richards, E.R., Venanzi, L.M., J. Chem. Soc. A 1966, 1707.Google Scholar
  35. 20.
    McWeeny, R.; Mason, R.; Towl, A.D.C. Discuss. Faraday Soc. 1969, 47, 20.CrossRefGoogle Scholar
  36. 21.
    Syrkin, Y.K. Bull. Acad. Sci. U.S.S.R., Classe Sci. Chim. 1948, 69.Google Scholar
  37. 22.
    For a review of MO treatments of the problems dealt with in in chapter, seeGoogle Scholar
  38. 23.
    For a different qualitative VB treatment of inorganic molecules, including “hypervalent” molecules, the reader is referred to the interesting work of Harcourt: Harcourt, R.D., “Qualitative Valence-Bond Description of Electron- Rich Molecules”, Lecture Notes in Chemistry, Vol. 30; Springer-Verlag: New York and Berlin, 1982.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1983

Authors and Affiliations

  • Nicolaos Demetrios Epiotis
    • 1
  1. 1.Department of ChemistryUniversity of WashingtonSeattleUSA

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