Sigma (σ) Bond: A sigma (σ) bond is formed by the end-to-end overlap of atomic orbitals, resulting in electron density along the internuclear axis.
Molecular Orbital Theory: A theory that describes the distribution of electrons in molecules in terms of combination and interaction of atomic orbitals forming molecular orbitals.
Cis-Trans Isomerism:\text{Isomerism arising from restricted rotation around double bonds or cyclic structures, leading to different spatial arrangements.}