%0 Journal Article
%A Katsyuba, Sergey A.
%A Griaznova, Tatiana P.
%A Vidiš, Ana
%A Dyson, Paul J.
%D 2009
%T Structural Studies of the Ionic Liquid 1-Ethyl-3-methylimidazolium Tetrafluoroborate in Dichloromethane Using a Combined DFT-NMR Spectroscopic Approach
%U https://acs.figshare.com/articles/journal_contribution/Structural_Studies_of_the_Ionic_Liquid_1_Ethyl_3_methylimidazolium_Tetrafluoroborate_in_Dichloromethane_Using_a_Combined_DFT_NMR_Spectroscopic_Approach/2863249
%R 10.1021/jp8083327.s001
%2 https://ndownloader.figshare.com/files/4561075
%K C 2 atom
%K imidazolium ring
%K chemical shifts
%K computation
%K NMR data
%K dichloromethane solutions
%K EMIM
%K Structural Studies
%K NMR spectroscopy
%K latter structures
%K C 5
%K anion
%K IL
%K NMR spectra
%K ion pairs
%X DFT methods in combination with NMR spectroscopy are used to investigate possible variants of the molecular structure of the ion pairs of the ionic liquid (IL) 1-ethyl-3-methylimidazolium tetrafluoroborate, [EMIM][BF4], in dichloromethane. According to the computations of the chemical shifts, experimental NMR spectra can be rationalized by an equilibrium between ca. 70−80% of structures with the anion positioned near to the C2 atom of the imidazolium ring and ca. 20−30% of structures with the anion close to the C5 and/or C4 atoms. The content of the latter structures, according to the computed Gibbs free energies, does not exceed 10%. Both the computations and the experimental NMR data suggest that the ratio of the two above-mentioned types of structures of the imidazolium-based ILs is influenced by the concentration/polarity of their dichloromethane solutions.
%I ACS Publications