Imidazolium-based ionic liquids are heterogeneous green solvents with complex microenvironments. Understanding the structural evolution of imidazolium-based ionic liquids with temperature is necessary to facilitate new applications of these green liquids. In its liquid phase, the solvent structure is assumed to be similar to their parent solids but with an increased degree of disorder. However, the change in structures of these liquids on a molecular level with experimental evidence is not clear. Through our research, we are able to report anomalous temperature-dependent vibrational changes at the C-2 position of 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF<sub>4</sub>]) when compared to other investigated imidazolium-based ionic liquids. Analysis of the infrared spectra, supported by simulation, suggests that there is a long-range ordering of this ionic liquid matrix upon heating which is counterinitiative to the conventional behavior of molecular liquids.

Temperature-dependent reorganization at the C-2 position of [EMIM][BF<sub>4</sub>]

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.

Temperature-dependent reorganization at the C-2 position of [EMIM][BF4]

Temperature-dependent reorganization at the C-2 position of [EMIM][BF₄]