This study investigates the intermolecular interactions and far-infrared (FIR) vibrational spectra of the ionic liquid (IL) 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Emim]+[NTf2]-). Density functional theory calculations were used to optimize 24 single ion-pair structures, while classical molecular dynamics simulations explored the liquid's cluster structure. The results highlight the role of C-H···N, C-H···O, and C-H···F hydrogen bonding in stabilizing the system. Experimental FIR spectra revealed absorption bands associated with hindered translational modes of cations and anions, as well as intramolecular wagging modes of anions, aligning well with computational predictions. The multiple ion-pair structures in the solvent model broadened the calculated peaks of the hindered translational modes and separated the two peaks of the wagging modes for the cis- and trans-anions. These findings pro- vide valuable insights into interaction of IL, enhancing our understanding of their structure for future applications.