ON THE RESONANCE THEORY

In the present paper, the mathematical formulation of resonance theory is discussed. In fact, resonance theory is a representative form of t he unitary group approach. Using the standard projection operator of t he symmetric group, a new basis for an irreducible representation of t he unitary group, called bonded tableau, can be constructed to describ e a resonance structure correspondingly. The relationships between bon ded tableau and Weyl tableaux and between valence bond and molecular o rbital approaches are revealed. Finally, test calculations on ozone an d benzene are performed.