A theoretical study on application of BN/CC isosterism to modify topology of coronene aromaticity and HOMO–LUMO energy gaps

Abstract

The change in local, semi-local and peripheral aromaticity of coronene upon gradual replacement of its peripheral CC bonds with BN bonds, starting from the C_3h symmetrical 3-BN derivative, was followed by calculating HOMA, PDI, FLU, EDDB and NICS-xy scans. They were calculated using B3LYP-D3(BJ), M06-2X and ωB97XD functionals, whose results agreed very well. It was found that introduction of BN units instead of CC units can, more or less, isolate aromatic carbocyclic subunits and increase peripheral electron delocalization. These subunits dominate the frontier orbital shapes and energy gap, thus enabling their modulation by applying BN/CC isosterism.