Fragmentation route of doubly ionized benzene, aniline, and nitroanilines monomers using a novel protocol from density functional theory and QTAIM

Abstract

The possibility of finding the fragmentation routes by theoretical methods led us to compare the molecular ions between neutral molecules of benzene, aniline, and o-, m-, and p-nitroaniline, using the density functional theory (DFT), under an aug-cc-pVDZ base set and a B3LYP exchange-correlation functional. After determining the structure and electronic energy of neutral and doubly ionized species, we used a new protocol based on analyzing Wiberg's binding indexes and the quantum theory of atoms in Bader molecules (QTAIM). The charge transfer and electronic distribution in aromatic monomers indicate the possibility of fragment formation in at least two pairs of carbon-carbon (CC) atoms. They show the possible loss of the -CNH₂ and -NO₂ groups in the aniline and nitroaniline molecules doubly ionized.

Keywords: Aromatic monomers; Fragmentation pathway; QTAIM analysis; Wiberg’s bond order indices.