Sigma (σ)

Definition

A sigma bond is a type of covalent bond where two atomic orbitals overlap directly between the nuclei of two atoms. It represents the strongest type of covalent chemical bond formed through the head-on (axial) overlap of atomic orbitals.

Related terms

Covalent Bond: A type of chemical bond where atoms share pairs of electrons to achieve stability.

Orbital Hybridization: The process by which atomic orbitals mix to form new hybrid orbitals that are degenerate in energy and suitable for the pairing of electrons to form chemical bonds.

Pi (π) Bond: A type of covalent bond formed by the side-to-side overlap of atomic orbitals, typically p-orbitals, lying above and below the axis connecting the bonded nuclei; it usually exists in conjunction with a sigma bond in double and triple bonded systems