ABSTRACT
The concept of hybridization was simultaneously created by L. Pauling, and J. C. Slater, According to IUPAC Gold Book, multiplicity is the number of possible orientations of the spin angular momentum corresponding to a given total spin quantum number. Before R. F. W. Bader et al., Pauling, also used the Hellmann-Feynman theorem to interpret the chemical bond in terms of the electrostatic force, although in a more basic manner. The original hybridization method is a reasonable tool to account for chemical bonds and geometric parameters. Resonance in chemistry began when Heisenberg incorporated Bose-Einstein statistics and Pauling, exclusion principle in his Quantum Matrix using the many-body problem for this purpose. The energy difference between the minimum at equilibrium geometry and the sum of energy of the isolated atoms at the dissociation limit is the bond dissociation energy, which is associated, in great part, with the resonance.
