In this study, two ionic liquids containing the bis(trifluoromethanesulfonyl)imide ([(CF 3 SO 2) 2 N − ]) anion are synthesized. The syntheses are based on an alkylation reaction of 1-methyl imidazole and 1,2-dimethyl imidazole followed by anion exchange. The obtained ILs are characterized by 1 H-NMR, 13 C-NMR, 19 F-NMR and FT-IR spectroscopy. Vibrational spectroscopy studies were conducted by infrared (FTIR/ATR), Raman spectroscopy and DFT calculations. The presence of methylation in the C2 position gives rise to specific marker bands in the Raman and IR spectra. In order to ascertain whether cation conformers are present in our ionic liquids, a computational study was performed using the density functional theory. The comparison of the experimental data and the computed spectra shows that three conformers of the imidazolium ions are present in both ionic liquids.

The synthesis of 5,5 '- (ethane-1,2-diylbis (azaneylylidene)) bis (3-undecyl-1,5-dihydro-4H-1,2,4-triazol-4-amine) and its Co (II) complex was carried out, and their structural spectroscopic properties were determined. The mode of bonding for the complexes was accomplished based on the elemental analysis, IR, UV-Vis, and NMR spectroscopy. Electronic structures and spectroscopic properties of the title compound were investigated from the calculative point of view. DFT/B3LYP optimization was performed based on the 6–31++G(d,p) basis set. In addition, the vibrational frequency analysis was performed with the optimized geometry at the same level of theory.