Regioselectivity of third-row maingroup dicarbides, C₂X (X = K-Br) for CO interaction: Fukui function and topological analyses

In this work, we present our calculations, based on density functional theory (DFT) to explore chemical reactivity of C₂X (X = K-Br) towards CO molecule. Computed condensed Fukui function (f^-)> reveals the carbon atom of C₂X (X = K-Br) to be the most active site for the CO interaction. This fact is also confirmed by the comparatively lesser average local ionization energy (I(r)¯) for the active carbon atom. Bader's topological parameters such as electron density ρ > 0.30 a.u. with negative ∇²ρ and H_BCP (total energy density) at the bond BCP of the carbon atoms of both C₂X (X = K-Br) and CO infers the CO interaction in all the cases to be of shared-kind.