For an ideal concerted movement of both particles, the ratio of the self-diffusion coefficients would be unity. At various temperatures, this ideal value can be reached for mixtures with salt mole fractions of 0.4 to 0.5. However, at low [Li][NTf 2 ] content, the self-diffusion of G3 is much larger than that of cations and anions. This is accounted for by the excess of free, noncoordinating G3 molecules moving significantly faster than the ones forming complexes with [Li] + cations.