Valence Bond Theory

Valence bond (VB) theory, developed by Heitler and London on the basis of wave mechanics and subsequently extended by Pauling and Slater, is a more advanced, quantum-mechanically grounded theory of covalent bond formation that goes beyond the simple Kossel-Lewis octet picture. It was put forward to account for newly discovered properties of compounds that the older, purely electron-counting approach could not explain, and — together with molecular orbital theory, introduced later in section 5.5 — represents the chapter's second major stage of bonding theory, moving from a static ele …