ABSTRACT
The denition of aromaticity and aromatic character of conjugated organic and inorganic systems has been of long-standing interest to chemists. Widely different properties such as molecular geometry, stabilization energy, and magnetic properties have been employed in the literature for characterizing aromaticity [1]. Yet there is no single measure for quantifying aromaticity. The general consensus is that aromatic molecules are planar and have equal bond lengths; they have 4n + 2 π electrons and large resonance energies. It is difcult to quantify aromaticity using any of these criteria. However, cyclic delocalization of mobile π electrons results in ring currents that are responsible for anomalous magnetic properties such as magnetic anisotropies, exalted magnetic susceptibilities, and large chemical shifts [2]. These properties appear to afford both a theoretical and an experimental way of quantifying aromaticity.
