Aromaticity and Magnetic Behavior in Benzenoids: Unraveling Ring Current Combinations

Chemistry. 2024 Jan 2;30(1):e202302415. doi: 10.1002/chem.202302415. Epub 2023 Nov 13.

Abstract

Nowadays, an active research topic is the connection between Clar's rule, aromaticity, and magnetic properties of polycyclic benzenoid hydrocarbons. In the present work, we employ a meticulous magnetically induced current density analysis to define the net current flowing through any cyclic circuit, connecting it to aromaticity based on the ring current concept. Our investigation reveals that the analyzed polycyclic systems display a prominent global ring current, contrasting with subdued semi-local and local ring currents. These patterns align with Clar's aromatic π-sextets only in cases where migrating π-sextet structures are invoked. The results of this study will enrich our comprehension of aromaticity and magnetic behavior in such systems, offering significant insights into coexisting ring current circuits in these systems.

Keywords: Clar's aromatic π-sextets; aromaticity; polycyclic benzenoid hydrocarbons; ring currents.