Hiickel's Rule Once the aromatic criteria is met, Huckel's rule applies. If the number of pi electrons is (4N 2) the compound is aromatic(where N is an integer) If the number of pi electrons is(4N)the compound is antiaromatic.Hückel’s Rule ❖Once the aromatic criteria is met, Huckel’s rule applies. ❖If the number of pi electrons is (4N + 2) the compound is aromatic (where N is an integer) ❖If the number of pi electrons is (4N) the compound is antiaromatic