If you are into large aromatic hydrocarbons, here is a new paper for you: "The Polyradical Character of Triangular non-Kekulé Structures, Zethrenes, p-Quinodimethane Linked Bisphenalenyl and the Clar Goblet in Comparison: An Extended Multireference Study," which just appeared in J. Phys. Chem. A. In this work we studied different bonding patterns for polycyclic hydrocarbons and how they lead to the formation of radical character. Some of the systems studied are based on phenalenyl:
For the other systems we studied, Clar's sextet rule comes into play. In an attempt to maximize the number of Clar sextets, the molecule creates empty valences somewhere else, leading to openshell character.
Macrocycles, flexibility and biological activity: A tortuous pairing - Here's an interesting paper from the Jacobson, Wells and Walsh labs at UCSF and Stanford that seeks to demonstrate how restricting the flexibility of macr...
3 days ago