| Abstract
| - Statistical analyses of quantitative definitions of aromaticity, ASE (aromatic stabilization energies),RE (resonance energies), Λ (magnetic susceptibility exaltation), NICS, HOMA, I5, and AJ, evaluatedfor a set of 75 five-membered π-electron systems: aza and phospha derivatives of furan, thiophene,pyrrole, and phosphole (aromatic systems), and a set of 30 ring-monosubstituted compounds(aromatic, nonaromatic, and antiaromatic systems) revealed statistically significant correlationsamong the various aromaticity criteria, provided the whole set of compounds is involved. Hence,broadly considered, the various manifestations of aromaticity are related and aromaticity can beregarded statistically as a one-dimensional phenomenon. In contrast, when comparisons arerestricted to some regions or groups of compounds, e.g., aromatic compounds with ASE > 5 kcal/mol or polyhetero-five-membered rings, the quality of the correlations can deteriorate or even vanish.In practical applications, energetic, geometric, and magnetic desriptors of aromaticity do not speakwith the same voice. Thus, in this sense, the phenomenon of aromaticity is regarded as beingstatistically multidimensional.
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