Sigma bond: sigma bond is formed due to the axial overlapping of two orbital’s (‘s-s’, ‘s-p’or’p-p’). Only one sigma bond can exists between two atoms. Sigma bond is denoted as’ σ ‘bond. In Sigma bond the electron density is maximum and it is cylindrically symmetrical about the bond axis. Free rotation about the sigma bond is possible. This bond can be independently formed, i.e., without the formation of a pi bond. Sigma bond is relatively strong as compared with Pi bond.
What is Sigma (σ) Molecular orbitals?
It is formed by the head-to-head overlap of atomic orbitals along inter-nuclear axis. The overlap region is maximum in this bonding. The orbital is symmetrical to rotation about inter-nuclear axis. Sigma molecular orbital forms a strong bond.
