After these synthetic efforts, we performed FTIR analyses on these imidazolium complexes, and the corresponding spectra are presented in Supporting Information Section II. Spectral features of Carbonate and Bicarbonate anions An anhydrous carbonate ion exhibits D3h symmetry and consequently manifests four distinct vibrations, characterized by strong peaks at approximately ~1420 cm-1 (CO symmetric stretch, typically within the range of 1275-1590 cm-1), 857 cm-1 (out-of-plane deformation, typically ranging between 810-906 cm-1), and 692 cm-1 (in-plane deformation, typically ranging between 670-756 cm-1).129-130. A symmetric CO stretch vibration for the carbonate ion is commonly reported to appear at around 1040-1105 cm-1. It has been demonstrated that upon coordination, the original symmetry is diminished, leading to the splitting of certain vibrations and the emergence of new bands in the resulting spectra. When the carbonate ion is coordinated in a bidentate fashion, the CO asymmetric stretch, which initially occurred around 1420 cm-1, bifurcates into two components: one at approximately 1270 cm-1 and another at the range of 1520-1570 cm-1. Bidentate carbonate complexes, such as [Co(en)2CO3]Cl, have exhibited notable absorbances at 1272 and 1281 cm-1, accompanied by an additional feature at 1577 cm1 129, 131. It has also been demonstrated that in the case of hydrogen carbonates, additional splitting of symmetric and asymmetric CO vibrations takes place. The asymmetric stretch shifts towards higher wavenumbers, leading to an absorption within the range of 1620-1660 cm-1. This specific asymmetric stretch has been attributed to carbonate groups with their oxygen atoms engaging in interactions with neighboring hydrogen atoms. Thus, it becomes evident that the way carbonates are coordinated and the environment they are solvated in, can give rise to distinct structural arrangements. Consequently, these variations in structure contribute to the observed differences in IR bands. In our FTIR analysis of the synthesized imidazolium carbonate and imidazolium bicarbonate salts, we have observed bands situated within specific
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