VSEPR Theory allows us to predict the shapes, bond angles, and polarity of a molecule, but it really doesn’t tell us why bonds form between atoms. A better understanding of Quantum Mechanics will allow us to understand why bonds form they way they do.
9.4 Quantum Mechanics and Chemical Bonding
In order to explain the reasons behind the observations in VSEPR Theory, valence bond theory was developed. Valence bond theory, which utilizes the overlap of atomic orbitals to explain bonding.
9.4 Orbital Overlap in Covalent Bonding