π-Hole interactions of group III-VIII elements-bearing dimers and trimers: a comprehensive ab initio study

Abstract

π-Hole interactions of group III-VIII fourth- and fifth-row elements-bearing molecules in the trigonal planar geometry with NCH Lewis base were comparatively investigated in the fashion of dimeric and trimeric forms. On this basis, the TrF₃/TF₂O/ZO₂F/YO₃/XO₂N/AeN₂O∙∙∙NCH and ∙∙∙(NCH)₂ complexes were utilized and subjected to a wide variety of ab initio computations. Basically, the electrostatic potential findings announced that all studied molecules had observable π-holes with variable sizes, which generally elevated according to the atomic size of the central atom (i.e., π-hole donor). From the energetic outcomes, all the studied complexes had significant interaction energy with values ranging from − 6.84 to − 35.49 kcal/mol, where more negative values were noticed for the trimeric complexes than the dimeric counterparts. Among the investigated complexes, the most favorable interaction energies were dedicated to the triel-bearing complexes. Quantum theory of atoms in molecules analysis assured the partial covalent nature for the majority of the investigated interactions. The calculated electronic parameters and global indices of reactivity confirmed the occurrence of π-hole interactions within the studied complexes. These annotations could be a cornerstone for upcoming crystal engineering and supramolecular chemistry experiments.