For the CHARMM parameters the accumulation of the neutral specie in the interleaflet is underestimated. The bilayer thickness of neutral MC3 in DOPC bilayers at 10 and 15 mol% IL (50 mM NaCl, 288 K) was experimentally determined to be 41 ± 3 and 40 ± 3 Å . For comparison we simulated the same compositions of MC3:DOPC under the same conditions and measured a bilayer thickness of 38.20 ± 0.27 and 39.61 ± 0.31 Å, respectively, aligning well with the experimentally in vitro determined values. Hence the increased accumulation of the neutral species observed in the CG simulations may not match entirely with the atomistic simulations but rather appears to agree well with the in vitro experimental data. These findings validate our model's ability to replicate the expected behavior across IL protonation states.