The model systems also include NaNO 3 as added salt and water molecules to complete the solution model. Initial solvation is performed using the GROMACS solvate tool. Three different salt concentrations, c s = 0.1, 0.3, and 0.5 M, respectively, corresponding to 30, 90, and 150 Na + and NO - 3 ion pairs are also examined. The number of water molecules varies between 1.4×10 4 and 1.6×10 4 , depending on the concentrations of DCPAM and NaNO 3 .