to potential artifacts stemming from baseline shifts 119. The prominently negative band at approximately 700 cm-1 could potentially be attributed to either the bending vibrational modes of -CF3 and -SNS groups 118, or the in-plane symmetrical/asymmetrical bending mode of the imidazolium cation's ring117. In the latter scenario, the negative absorption peak indicates a modification in the bending mode of the cation within the electronic double layer. In accordance with Noack et al. 117, the positive features centered around 1445 cm-1 and 1430 cm-1, near 1440 cm-1, can be associated with the asymmetrical stretch of the imidazolium ring in-plane, the CH3(N) stretch, and the symmetrical bending mode of NC(CH3)N-HCH within the imidazolium ring. However, it is important to account for potential overlap of these absorbances with those originating from acetonitrile, which might be manifested as peaks at 1447 cm-1 (antisymmetric CH3 deformation) and 1378 cm-1 (symmetric CH3 deformation) 120. The positive band observed at 1580/1590 cm-1 can be confidently attributed solely to the symmetrical and asymmetrical in-plane modes of stretch, namely the CH2(N) and CH3(N)CN modes, occurring within the imidazolium ring. Additionally, the peak at approximately 1540 cm-1 can be associated with the C-CH3 bond within the ring and can be attributed to the NC(CH3)NCC stretch mode of the cation 2, 3, 6. The combination of these two peaks results in a composite peak centered around 1560 cm-1 (as depicted in Figure 6.1). The prominent positive peaks located at 2851 cm-1 and 2919 cm-1 can be confidently attributed, respectively, to the symmetrical stretching mode of the -CH2 group and the symmetrical stretching mode of the -CH3 group within the alkyl chain of the cation. Furthermore, the positive feature observed at 2950 cm-1 can be assigned to the asymmetric stretch of the -CH3 group in the alkyl chain 1 The conjunction of positive characteristics corresponding to the imidazolium cation and negative attributes associated with the NTf2 anion implies a substitution occurring within the electronic double layer. However, this substitution might not necessarily indicate complete anion depletion. Rather, it suggests a modification in
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