Author(s)

Gholam Hossein Shafiee

Department of Chemistry, Islamic Azad University of Abadeh, Abadeh, Iran.

In this report, different models of bonding and structure such as Lewis, VSEPR, Ligand close packing (LCP), VB, qualitative MO and QTAIM have been applied to analyze the Bonds and structures of two equilibrium geometries (planar D_2h and perpendicular D_2d) of C₂H₄²⁺. The geometries were optimized at near RHF and MP2 limit using ccpVTZ basis set. While the above bonding models are successfully applied for predicting the low energy isomers of molecules, prior to solving the Schr?dinger equation, it is shown that the cited models fail in predicting the existence of perpendicular, D_2d form of C₂H₄²⁺. In this regard the interpretations of significant energetic stabilization of D_2d form over planar isomer has also been revisited. This is attributed to the hidden effect of the Pauli Exclusion principle.

C₂H₄²⁺; LCP; Hyperconjugation; QTAIM; Pauli Exclusion Principle

G. Hossein Shafiee, "Conformational and Bonding Analysis of C₂H₄²⁺," Open Journal of Physical Chemistry, Vol. 2 No. 3, 2012, pp. 176-181. doi: 10.4236/ojpc.2012.23023.