new aromaticity index is proposed based on the energy of π orbital [π1 + (π1 - π2) + (π1 - π3)]. Calculations
have been performed on aromatic and heteroaromatic compounds by using DFT method at B3LYP/6-311G+(d,p) level.
This new index has been tested on 6π electron compounds and compared with the experimental resonance energy (ERE),
the Bird index (Ix), the molar magnetic susceptibility (ΧM), the aromatic stabilization energy (ASE), and the isomerization
stabilization energy (ISE). In all the cases, a good correlation has been found.