THEORETICAL RELATIONSHIP BETWEEN DIAMAGNETIC SUSCEPTIBILITY EXALTATION AND AROMATIC STABILIZATION

The London theory of diamagnetism for aromatic compounds was reformulated by analogy with the graph theory of aromaticity. A relationship between diamagnetic susceptibility exaltation (DSE) and aromatic stabilization was theoretically clarified for these compounds. The role of the applied magnetic field was to make the total π-electron energy of a conjugated system slightly approach that of its olefinic reference structure. The total π-electron energy of the reference structure was free from the effect of the magnetic field. The DSE was found to reflect the sign of the resonance energy and, to a lesser extent, its magnitude. Now, we can safely use the DSE as a definite criterion of aromaticity. © 1979, American Chemical Society. All rights reserved.