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Nitrogen inversion barriers in three-membered rings. An ab initio molecular orbital study

✍ Scribed by M. Alcamí; J. L. G. De Paz; M. Yáñez

Publisher
John Wiley and Sons
Year
1989
Tongue
English
Weight
982 KB
Volume
10
Category
Article
ISSN
0192-8651

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✦ Synopsis

Polarization and correlation effects on the nitrogen inversion barrier of some three-membered rings have been investigated. The characteristics of the barrier have been analyzed in terms of perturbation theory arguments. This analysis shows that the HOMO is the orbital that changes more dramatically along the inversion barrier. As a consequence, there is a good linear correlation between the destabilization undergone by the HOMO along the pyramidalization process and the barrier height. To obtain quantitatively meaningful barriers it is necessary to use polarized basis sets. Although polarization effects at the inverting center are dominant, a proper polarization of the remaining atoms of the ring seems also necessary. In general, with the only exception of 1H-diazirine, correlation effects on the barrier height are small if a polarized basis set is used.

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