Figure 4.

Density profiles along the membrane normal (from the top): CHARMM36, CHARMM-Drude2017, CHARMM-Drude2023, AMOEBA, and ECClipids. In the third column, the Cl^– densities are shown in the same color as their cations in the first and second columns. Note that for CaCl₂, 350 mM (Drude models and ECC) and 450 mM (AMOEBA and CHARMM36) concentrations are shown; while for NaCl, 1000 mM concentration is shown for all force fields except CHARMM36 (950 mM NaCl). The CHARMM36 data are reproduced using the Zenodo repositories of refs (123−126), ECC using the Zenodo repository of ref (127). Data are from POPC simulations for all force fields other than AMOEBA (DOPC).