A comparative investigation for the versatility of sp 2-hybridized trivalent triel-containing molecules to engage in � π-hole interactions with Lewis base, Lewis acid, σ-hole-containing molecules, and lp-hole-containing molecules was dwelled using quantum mechanical calculations. According to the results, it was found that the À π-hole interactions were more favorable than the + π-hole ones, with larger negative interaction energies and shorter intermolecular distance. + π-hole interactions with lp-hole-containing molecules were observed with larger substantial interaction energies than Lewis acids, and σ-hole-containing molecules varied from-0.65 to-5.18 kcal/mol. Quantum theory of atoms in molecules and noncovalent interaction index analyses revealed the noncovalent nature for � π-hole interactions. As well, symmetry-adapted perturbation theory-based energy decomposition analysis affirmed that electrostatic and dispersion forces controlled the À π-hole interactions, whereas the + π-hole analogs were dominated by dispersion forces only. These findings will be of advantage to the forthcoming studies in the materials and supramolecular chemistry.

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The efficacy of pure and aluminum (Al)-doped boron nitride nanocarriers (B12N12 and AlB11N12) in adsorbing Chlormethine (CM), an anti-cancer drug, was comparatively dissected by means of the density functional theory method. The CM∙∙∙B12N12 and ∙∙∙AlB11N12 complexes were studied within two configurations, A and B, in which the adsorption process occurred via N∙∙∙ and Cl∙∙∙B/Al interactions, respectively. The electrostatic potential affirmations confirmed the opulent ability of the studied nanocarriers to engage in delivering CM via two prominent electrophilic sites (B and Al). Furthermore, the adsorption process within the CM∙∙∙AlB11N12 complexes was noticed to be more favorable compared to that within the CM∙∙∙B12N12 analog and showed interaction and adsorption energy values up to –59.68 and −52.40 kcal/mol, respectively, for configuration A. Symmetry-adapted perturbation theory results indicated that electrostatic forces were dominant in the adsorption process. Notably, the adsorption of CM over B12N12 and AlB11N12 nanocarriers exhibited predominant changes in their electronic properties. An elemental alteration was also revealed for the softness and hardness of B12N12 and AlB11N12 nanocarriers before and following the CM adsorption. Spontaneity and exothermic nature were obviously observed for the studied complexes and confirmed by the negative values of thermodynamic parameters. In line with energetic manifestation, Gibbs free energy and enthalpy change were drastically increased by the Al doping process, with values raised to –37.15 and –50.14 kcal/mol, respectively, for configuration A of the CM∙∙∙AlB11N12 complex. Conspicuous enhancement was noticed for the adsorption process in the water phase more than that in the gas phase and confirmed by the negative values of the solvation energy up to −53.50 kcal/mol for configuration A of the CM∙∙∙AlB11N12 complex. The obtained outcomes would be the linchpin for the future utilization of boron nitride as a nanocarrier.

In the current study, σ‐hole interactions of group IV–VIII element‐containing molecules in tetrahedral geometry with Lewis bases were comparatively scrutinized. The FSiF3, OPF3, NSF3, FClO3, and OArO3 molecules were devoted as Lewis acid centers to interact with NH3 and NCH Lewis bases. According to the results, the most significant σ‐hole interactions were ascribed to the FSiF3⋅⋅⋅ and FClO3⋅⋅⋅Lewis base complexes with interaction energy up to –29.74 kcal mol−1 in the case of the FSiF3⋅⋅⋅NH3 complex. Symmetry‐adapted perturbation theory‐based energy decomposition analysis (SAPT‐EDA) demonstrated that the electrostatic energy (Eelst) was the most prevalent force dominating the explored interactions, while the exchange energies exhibited unfavorable contribution. Quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) results emphasized the closed‐shell nature for all the investigated complexes except FSiF3⋅⋅⋅NH3 complex that demonstrated a covalent nature. Crucially, the utilization of the positively‐ and negatively‐directed external electric field (EEF) led to amelioration and debilitation of the strength of the studied interactions, respectively. The present findings provide knowledge essential to further expanded applications in the fields pertinent to materials science and crystal engineering.

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The effects of Lewis basicity and acidity on σ-hole interactions were investigated using two sets of carbon-containing complexes. In Set I, the effect of Lewis basicity was studied by substituting the X3/X atom(s) of the NC-C6H2-X3 and NCX Lewis bases (LB) with F, Cl, Br, or I. In Set II, the W-C-F3 and F-C-X3 (where X and W = F, Cl, Br, and I) molecules were utilized as Lewis acid (LA) centers. Concerning the Lewis basicity effect, higher negative interaction energies (Eint) were observed for the F-C-F3∙∙∙NC-C6H2-X3 complexes compared with the F-C-F3∙∙∙NCX analogs. Moreover, significant Eint was recorded for Set I complexes, along with decreasing the electron-withdrawing power of the X3/X atom(s). Among Set I complexes, the highest negative Eint was ascribed to the F-C-F3∙∙∙NC-C6H2-I3 complex with a value of −1.23 kcal/mol. For Set II complexes, Eint values of F-C-X3 bearing complexes were noted within the −1.05 to −2.08 kcal/mol scope, while they ranged from −0.82 to −1.20 kcal/mol for the W-C-F3 analogs. However, Vs,max quantities exhibited higher values in the case of W-C-F3 molecules compared with F-C-X3; preferable negative Eint were ascribed to the F-C-X3 bearing complexes. These findings were delineated as a consequence of the promoted contributions of the X3 substituents. Dispersion forces (Edisp) were identified as the dominant forces for these interactions. The obtained results provide a foundation for fields such as crystal engineering and supramolecular chemistry studies that focus on understanding the characteristics of carbon-bearing complexes.

σ-Hole and lone-pair (lp)-hole interactions within σ-hole···σ-hole, σ-hole···lp-hole, and lp-hole···lp-hole configurations were comparatively investigated on the pnicogen···pnicogen homodimers (PCl 3 ) 2 , for the first time, under field-free conditions and the influence of the external electric field (EEF). The electrostatic potential calculations emphasized the impressive versatility of the examined PCl 3 monomers to participate in σ-hole and lp-hole pnicogen interactions. Crucially, the sizes of σ-hole and lp-hole were enlarged under the influence of the positively directed EEF and decreased in the case of reverse direction. Interestingly, the energetic quantities unveiled more favorability of the σ-hole···lp-hole configuration of the pnicogen···pnicogen homodimers, with significant negative interaction energies, than σ-hole···σ-hole and lp-hole···lp-hole configurations. Quantum theory of atoms in molecules and noncovalent interaction index analyses were adopted to elucidate the nature and origin of the considered interactions, ensuring their closed shell nature and the occurrence of attractive forces within the studied homodimers. Symmetry-adapted perturbation theory-based energy decomposition analysis alluded to the dispersion force as the main physical component beyond the occurrence of the examined interactions. The obtained findings would be considered as a fundamental underpinning for forthcoming studies pertinent to chemistry, materials science, and crystal engineering.