Hybridization in Benzene [ENDORSED]

[Russell Chuang 1J]

For benzene, the three dimensional model has a circle of orbitals above and below the actual ring. Why does that occur?

[Hudson2J]

Because each carbon has 3 regions of electron density around it, they all exhibit sp2 hybridization. Each carbon also has 4 valence electrons, meaning they need an additional spot for the remaining electron. This electron goes in the unhybridized 2p orbital, which visually appears to be a region of electron density above and below the ring of carbon atoms.

[KyleNagasawaDisc3C_Chem 14B2022W_]

Hey Hudson,

Please recall that, according to the VB Hybridization model, the carbon atoms of benzene have adjacent p orbitals with parallel axis to best allow for delocalization of the pi electrons within the ring to allow for aromaticity. When the molecular orbitals of benzene are represented, the p orbitals are shown with the different phase regions on top and on the bottom of the planar ring. In terms of rationalizing this, you need to account for the optimal overlap of p orbitals occurring when they are oriented with the fixed parallel axis in addition to the general shape of the p orbitals.