Aromaticity and Induced Current Study of C8H8( n+2) (n = −6, −4, −2, 0): In the Viewpoint of Huckel’s Rule

Abstract

The (4n+2)π aromatic systems are studied in variants of C₈H₈^(
n+2) (n = −6, −4, −2, 0) via the localized orbital localization (LOL) and the electron localized function (ELF) by considering the induced current density. In this work, a four-electron dia-tropic (aromatic) ring current for (4n+2)π variants of C₈H₈^(
n+2) (n = −6, −4, −2, 0) and a two-electron paratropic (anti-aromatic) current for (4n)π arepredicted. With the HOMO and LUMO energies and also the HOMO/LUMO overlap in the whole space, it is possible to predict the transition states from delocalized currents in carbocyclic compounds to nitrogen-localized currents in all heterocyclic compounds in viewpoint of aromaticity and antiaromaticity. In addition, NICS and SNICS values confirm the degree of aromaticity and antiaromaticity in these rings.