An Infrared Spectroscopy Study of the Conformational Evolution of the Bis(trifluoromethanesulfonyl)imide Ion in the Liquid and in the Glass State

Figure 3

Measured infrared absorption of DEBA-TFSI as a function of temperature (panel (e), curves are stacked for clarity). The symbols refer to the attribution of the lines to trans-TFSI (red), cis-TFSI (blue), and cation (green) vibrations. For comparison purpose, the absorptions of TMPA-TFSI and TMHA-TFSI measured at 160 K are shown in panel (f) with the attribution of lines (same symbols used for DEBA-TFSI) [17]. In panels (a)–(d) absorptions of single ions in the frequency range between 150 and 460 cm⁻¹ calculated with the various combinations of theories and basis sets are reported. No scaling factor was used.