Illustrated Glossary of Organic Chemistry

Electron delocalization (delocalization): Distribution of electron density beyond a fixed place such as a single atom, lone pair, or covalent bond via resonance or inductive effects.

The oxygen lone pairs of ethoxide ion are not delocalized.


The oxygen lone pairs of trifluoroethoxide ion are delocalized via the trifluoromethyl group's electron-withdrawing inductive effect (symbolized by arrows).

One of the five oxygen lone pairs and the carbonyl pi bond electrons of acetate ion is delocalized by resonance.

The six pi electrons of benzene are delocalized by resonance.