How does electron delocalization help explain bonding in benzene?

In chemistry, electron delocalization is fundamental to understanding the structure and stability of benzene. Rather than having localized double bonds between specific pairs of carbon atoms, the six $\pi$ electrons in benzene are shared across the entire six-carbon ring.12

Bonding and Stability

• Molecular Orbital (MO) Theory: The six carbon atoms contribute their 2p orbitals to form a system of $\pi$ molecular orbitals that extend over the entire molecule. Because these orbitals are delocalized, the bonding effect of each electron pair is distributed across multiple atoms rather than being restricted to two. This distribution allows the electrons to be more strongly held by the attractive force of all six carbons, contributing to the molecule's significant stability.321
• Resonance Theory: According to the theory of resonance, benzene is a resonance hybrid of multiple structures. This model explains why all carbon-carbon bonds in benzene are of equal length (1.40 angstroms), a value intermediate between standard single and double bonds.41

This delocalization results in a molecule that is significantly more stable and less reactive than a localized conjugated triene, as the electrons occupy low-energy bonding orbitals without filling antibonding ones.31