The value of T 1 was then determined for bulk solutions of NaCl and Na 2 SO 4 at varying salt concentration c s . Both MD simulations and MRI experiments show a decrease of T 1 upon increasing the concentration of either salt (Fig. ). In the case of NaCl, our simulations underestimate T 1 for all salt concentrations c s , with a maximum difference of ≈ 14 % for c s = 4 mol/kg. For Na 2 SO 4 , the value of T 1 from experiments was found to decrease faster with c s as compared with the MD value, with T 1 value at c s = 1 mol/kg being overestimated by the simulations, while the T 1 value at c s = 0 mol/kg is being underestimated. These slight differences in T 1 between experiments and simulations for both NaCl and Na 2 SO 4 salt solutions could be the consequence of the parametrization of the ion force fields that are based solely on thermodynamics quantities: the ion solvation energy as well as the ionic activity are matched to their respective experimental counterparts (see Ref. as well as the Supplemental Material), whereas T 1 is a dynamic property that is sensitive to the molecular motions (i.e., to the viscosity of the fluid).