pi electron

This term is a specialized technical expression used exclusively within chemistry and physics to describe a specific type of electronic distribution. It refers to electrons located in orbitals that are perpendicular to the plane of the atomic nuclei, creating a cloud of electron density above and below the bond axis.

In a professional scientific context, the term is often used to explain the properties of aromatic compounds and conjugated systems. It is distinct from sigma electrons, which form the primary single bonds of a molecule.