Figure and S25 shows the density across the bilayer normal for the DUM3/MP and DUK2/KP headgroups in both the atomistic and corresponding CG systems. At low pH the IL is assumed fully charged, while at high pH it is neutral. As confirmed by the snapshots of the simulations highlighted in Figure , the IL maintains a lamellar topology at low pH (charged headgroup), while at high pH (neutral headgroup) it accumulates in between the POPC leaflets, generating the expected oil lens. This behaviour aligns well with the knowledge in the literature, where neutral MC3 and cholesterol are concluded to form an oil core within LNPs, while multilamellar and inverse hexagonal phases are proposed to form under low pH when ILs are charged . Additional results from atomistic simulations also indicate the same behavior .