(2), 5.7 (5), and 6.1 eV ( )). However, the E(n,*) values also vary with the n orbital energies as this orbital is of very low energy for 5 and 6 being HOMO-2 at 2.09 and 1.78 eV below the highest occupied -orbital (HOMO), but high for 3 and 4 (for 3 it is as much as 1.89 eV above the highest occupied -orbital, which is HOMO-1). Also, the highest  and lowest * orbital energies vary between the heteroaromatics (Table ). As a result, for 3 the energy differences between the n and the b1 * orbital versus the highest  and the b1 * orbital are 7.77 and 9.66 eV, while for 5 these energy differences are 10.44 and 8.36 eV, respectively. Thus, electronegativity variations among the E atoms impact strongly on the n,* excitation energies, which are not necessarily related to (anti)aromatic character.