Aromaticity of neutral and doubly charged polyacenes

Toshimasa Ishida1, Jun-ichi Aihara

  • 1Fukui Institute for Fundamental Chemistry, Kyoto University, Takano-Nishibirakicho, Kyoto, Japan.

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Like benzene, cyclobutadiene and cyclooctatetraene are cyclic compounds with alternate single and double bonds. However, their chemical behavior differs from benzene, as they are unstable and not aromatic. So, what are the structural characteristics of unsaturated compounds categorized as aromatic?
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