Structural analysis of water in ionic liquid domains - a solvent study for β-NMR
Katarzyna Maria Dziubinska-Kuhn
Liquid-state β-NMR spectroscopy allows to implant short-lived isotopes of alkali metals directly into a liquid host in high vacuum environment. Detected asymmetry represents the on- and off-resonance response of the implanted atoms to an applied magnetic field and can be used to obtain detailed information about chemical environment of the implanted short-lived isotope. This contribution will present the results of β-NMR measurements performed on 26Na isotope in imidazolium-based Ionic Liquids with short side alkyl chains, such as BMIM-HCOO and EMIM-DCA, together with complementary 1D and 2D NMR measurements and MD simulations.
Recent studies revealed that small aggregations of water molecules can become well isolated and vacuum-stable in specific types of ILs. One of the most studied examples are imidazolium salts able to form networks based on the cation-anion interactions and trap water molecules in between. This behaviour of ILs is especially important for their electrochemical properties, which can be significantly improved by the presence of water in the solvent.