When comparing the salt-dependent swelling against the theoretical model, represented by solid lines, we can see that it clearly captures the expected behavior, but with quantitative differences. Firstly, we notice that the theoretical estimations of ζ a are closer to the ideal value. The reason for this discrepancy is the additional electrostatic interactions/correlation effects that are accounted for in the simulations and that lead to a larger energetic penalty being associated with highly ionized states. We further note that the swelling ratio is well captured by the theoretical model, presenting a clear maximum, especially for the largest values of N . Finally, the behavior of Z net is qualitatively captured by the theoretical model, with discrepancies in the location of the maximum, which is shifted to larger c res salt for the theory. The theoretical predictions in solid lines correspond to different a 0 than the cases in Fig. . Using the same parameters instead results in the dotted lines, which display more pronounced differences to the simulation results.