Bond Orbital Theory of Chemical Reactivity

反應性의 結合 Orbital 理論

  • Yang, Kang (Radiation Laboratory Continental Oil Company Ponca City) ;
  • Ree, Tai-Kyue (Department of Chemistry, University of Utah)
  • Published : 19640300

Abstract

The linear combination of bond orbitals method is used to investigate the reactivity of halomethanes in abstraction reactions by atoms. The activation energy is evaluated on the assumption that, in an activated complex, two electrons in a bond to be broken become completely isolated from the rest of the ${\sigma}$-electron systems. Such a model leads to an intuitively attractive concept that the interactions between the reactive bond and the neighboring bonds govern the reactivity of ${\sigma}$-electron systems. The resulting equation for the activation energy, ${\varepsilon},\;is:\;{\narepsilon}= ${\varepsilon}={\zeta}+$$${\sum}_{i=1}^3$${\eta}c-I,$ c-4 Here, subscript C-4 indicates the bond to be broken, while C-i represents the other three bonds surrounding the reactive bond; ξ is the activation energy of a hypothetical reaction of an isolated C-4 bond and an attacking atom; and ${\eta}$C-i,C-4 stems from the stabilizing interacting of C-4 bond with neighboring C-i bonds. A choie of η′s consistent with bond strength data simplifies the above equation to a form ${\varepsilon}={\zeta}\;+\;N{\eta}c$-H, C-4 where N denotes the number of C-H plus C-F bond in halomethanes. In agreement with this equation, experimental -values increase linearly with increasing N.

Keywords

References

  1. Quantum Chemistry R. Daudel;R. Lefebvre;C. Moser
  2. Ann. Rev. Phys. Chem. v.12 T. Fueno
  3. J. Chem. Soc. C. A. Coulson
  4. J. Am. Chem. Soc. v.84 K. Yang
  5. J. Phys. Chem. v.67 K. Yang
  6. J. Chem. Phys v.38 K. Yang
  7. proc. Roy. Soc. (London) v.A205 G. G. Hall
  8. J. Chem. Soc. R. D. Brown
  9. The Theory of Equations H. W. Turbull
  10. T. Ree
  11. J. Chem. Phys v.18 M. Szwarc
  12. Z. Physik Chem. v.B23 E. Cremer;J. Curry;M. Polany
  13. J. Chem. Phys v.6 J. E. Vance;W. C. Bauman
  14. Trans. Faraday Soc. v.36 J. N. Haresnape;J. M. Stevels;E. Warhurst
  15. J. Phys. Chem. v.59 J. F. Reed;B. S. Rabinovitch
  16. Quart. Rev. v.5 E. Warhurst
  17. J. Am. Chem. Soc. v.64 G. W. Wheland
  18. J. Phys. Chem. v.61 J. F. Reed;B. S. Rabinovitch
  19. Trans. Faraday Soc. v.32 W. Heller;M. Polany