Molecular Interactions in [PhMT][X] Ionic Liquid: Structures, Binding Energies and Topological Properties

Ionic liquids have attracted significant attention in the literature owing to their ubiquitousapplications in diversifying areas of modern chemistry, materials science, and biosciences [1, 2].The present work focuses on unraveling the molecular interactions underlying [PhMT] [ X] ILs.The hydrogen bond formed between cation phenyl methyl triazolium [PhMT+] and the anions([X]− = [Cl−], [ClO4−], [CH3CO2 −], [CF3CO2−], [NO3−], [N(CN)2−], [N(CN)3−], [NTF2−], [PF6−]and [BF4−]) have been investigated using MP2 method [3] in conjunction with the aug-cc-pVDZbasis set [4]. The structural, binding energy, topological properties of electron density, naturalcharges and charge transfer values were calculated. Ion pairs (IPs) have electronic bindingenergies (BEs) in the range of −108.45 to −80.70 kcal/mol at MP2/aug-cc-pVDZ level. Theresults show that the trend of interactions is IPs [CH3CO2−] > [Cl−] > [NO3−] > [CF3CO2−] > [BF4−] > [ClO4−] > [N(CN)2−] > [PF6−] > [NTF2−] > [N(CN)3−]. The charge analysis was doneusing natural bond orbital (NBO) analysis. The nature of intermolecular interactions in the[PhMT][X] was characterized by Bader s quantum theory of atoms in molecules (QTAIM)method [5].

Keywords:

Hydrogen Bonds , Atoms in Molecules , Phenyl Methyl Triazolium , Topological Properties