A self-assembled cobalt molecular grid of a pyrazine-bridged bis-tridentate ligand (LR), where R = H (1), CH3 (2), and Br (3), was prepared and structurally characterized. Depending on the electronic effects of the substituents on the ligand, the redox of the metal center was systematically modulated, and the magnetic behavior from essentially high-spin CoII in 3 versus completely diamagnetic CoIII in 1 to CoII spin-crossover in 2 can be achieved.

The controversial proposal that substituent effects in cation–π interactions can be attributed mainly to electrostatic effects between the ion and local dipoles has been theoretically studied by analyzing 171 aromatics interacting with Na+. Our results stress the importance of both electrostatic and π-polarization effects to properly describe cation–π interactions.

The controversial proposal that substituent effects in cation–π interactions can be attributed mainly to electrostatic effects between the ion and local dipoles has been theoretically studied by analyzing 171 aromatics interacting with Na+. Our results stress the importance of both electrostatic and π-polarization effects to properly describe cation–π interactions.