Microscopic interactions of the imidazolium-based ionic liquid with molecular liquids depending on their electron-donicity

• DOI: 10.1039/c4cp03565h
• Publication Date: 2014-09-11T10:13:45Z
• Authors: Toshiyuki Takamuku; Hiroshi Hoke; Abdenacer Idrissi; Bogdan A. Marekha; Myriam Moreau; Yusuke Honda; Tatsuya Umecky; Takuya Shimomura
• Keywords: [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry; [CHIM.THEO] Chemical Sciences/Theoretical and/or physical chemistry; 01 natural sciences; 0104 chemical sciences

Microscopic interactions of an imidazolium-based ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (C2mimTFSI), with dimethyl sulfoxide (DMSO), methanol (MeOH), and acetonitrile (AN) have been analyzed by means Raman, attenuated total reflectance infrared (ATR-IR), (1)H (13)C NMR spectroscopy techniques. The magnitude the red-shift C(2)-H vibration mode imidazolium ring deshielding hydrogen carbon atoms, compared that other atoms or anion, indicated a strong interaction between atom molecular liquids in following order; DMSO ≫ MeOH > AN. This correlates order electron donicities these which allows us to suggest bonding character interactions. behavior S= O as function molar fraction xDMSO also suggested molecules are stoichiometrically hydrogen-bonded three C(2,4,5)-H, ring. In contrast, C(4,5)-H is much weaker than DMSO. AN hardly forms bonds atoms. Instead, may interact through π-π interaction. lead loosening TFSI anion from cation; this both blue-shift S=O stretching trifluoromethyl increase liquid xML. latter weak solutions, be explained possible hydroxyl group electron-acceptor anion. Furthermore, organization around ethyl methyl groups cation discussed terms chemical shift