◆ 奠 l0元-electrons The two major(neutral)resonance forms for azulene... Aromatic “cyclopentadiene ⊕ “cycloheptatriene Zwitterionic anion-like” cation-like” 两性离子的 ...and the very stable Zwiterionic form. ◆ 薁 Zwitterionic 两性离子的