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Baird’s rules at the tipping point

This year marks the 50th anniversary of Baird’s rules of aromaticity — a set of perturbational molecular orbital theory analyses that has garnered considerable attention in the past ten years in light of its many real-world applications in photochemistry.

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Fig. 1: Baird’s rule is a reversal of the Hückel electron-counting rule for aromaticity and antiaromaticity in the S1 and T1 ππ* states.


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Correspondence to Lucas J. Karas or Judy I. Wu.

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Karas, L.J., Wu, J.I. Baird’s rules at the tipping point. Nat. Chem. 14, 723–725 (2022).

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