Guidelines for Tuning the Excited State Hückel–Baird Hybrid Aromatic Character of Pro‐Aromatic Quinoidal Compounds**

Pro-aromatic molecules have higher-energy diradicaloid states that are significantly influenced by resonance structures in which conjugated rings take on Hückel-aromatic character. Recently, it has been argued there also pro-aromatic adopt central units with 4nπ-electron Baird-aromatic character the T1 state, although detailed analysis suggests these compounds better labelled as Hückel–Baird hybrid where Hückel-aromaticity dominates. Herein, we consider a series of symmetrically substituted potential Baird aromaticity lowest excited triplet and singlet states. Our computational results allow us to establish general guidelines for rational design state Hückel/Baird quinoidal compounds. We found two main strategies promote high aromatic character: 1) anionic small electron donating groups substituents exocyclic withdrawing substituents, or 2) deficient electron–donor substitution.