Nuclear magnetic resonance studies on the rotational and translational motions of ionic liquids composed of 1-ethyl-3-methylimidazolium cation and bis(trifluoromethanesulfonyl)amide and bis(fluorosulfonyl)amide anions and their binary systems including lithium salts

摘要: Room temperature ionic liquids (ILs) are stable composed of anions and cations. 1-ethyl-3-methyl-imidazolium (EMIm, EMI) is a popular important cation that produces thermally ILs with various anions. In this study two amide-type anions, bis(trifluoro-methanesulfonyl)amide [N(SO(2)CF(3))(2), TFSA, TFSI, NTf(2), or Tf(2)N] bis(fluorosulfonyl)amide [(N(SO(2)F)(2), FSA, FSI] were investigated by multinuclear NMR spectroscopy. addition to EMIm-TFSA EMIm-FSA, lithium-salt-doped binary systems prepared (EMIm-TFSA-Li EMIm-FSA-Li). The spin-lattice relaxation times (T(1)) measured (1)H, (19)F, (7)Li spectroscopy the correlation (1)H NMR, τ(c)(EMIm) (8 × 10(-10) 3 10(-11) s) for librational molecular motion EMIm those τ(c)(Li) (5 10(-9) 2 lithium jump evaluated in range between 253 353 K. We found bulk viscosity (η) versus diffusion coefficient D(EMIm) rate 1/τ(c)(EMIm) have good relationships. Similarly, linear relations obtained η D(Li) 1∕τ(c)(Li). mean one-jump distances Li calculated from D(Li). experimental values coefficients, conductivity, viscosity, density our previous paper analyzed Stokes-Einstein, Nernst-Einstein, Stokes-Einstein-Debye equations neat clarify physicochemical properties mobility individual ions. deviations classical discussed.