Delocalization of Electrons
Section 14.3
Introduction
Delocalization allows the pi electrons to spread over more than two nuclei
This spreading out of the electrons gives the species a lower potential energy making it more stable
Best example is with benzene The molecule is a planar hexagonal shape Each carbon atom is sp2 hybridized
More about Benzene
One of the sp2 orbitals forms a sigma bond with H Two other orbitals forms sigma bonds with the C on
each side The remaining electron is in a p-orbital
perpendicular to the plane of the sigma bonds These p-orbitals on each C atom interact to produce
a delocalized pi bond The ring has high electron density above and below
the ring
Benzene Ring
Ethene (C2H4) Benzene (C6H6)
More
Resonance hybrids show delocalization of electrons which leads to: Greater stability and an intermediate bond length
and strength Less reactivity Ability to conduct electricity (because electrons are
more free to move, i.e. delocalized)