The initial structure of the MMS and MMU systems are generated with packmol software. Both the leaflets contain equal number of lipid molecules. We have taken 193 lipids per leaflet. The membranes are solvated with 16364 water molecules (around 42 water molecules per lipid, a reasonable hydration level for a fully hydrated system). We have also added 120 Na ions for charge neutralisation. NM, MMS and MMU membranes are parameterised with CHARMM36 all-atom forcefield since it provides the structure and dynamics in good agreement with the experimental data. The forcefield for the NM membrane lipids are obtained from literature. The MMS and MMU membrane lipid forcefields are obtained from CHARMM-GUI input generator . For water molecules we have chosen CHARMMmodified TIP3P water model (also known as mTIP3P/TIPS3P). In the biomolecular simulations containing proteins or lipids the TIP3P and mTIP3P water models are more accepted and appreciated over other models since CHARMM36 lipid forcefield is optimised with mTIP3P, and use of other water models may lead to inconsistencies in membrane properties used . Although the TIP4P model provides excellent results for the bulk water systems, it was not preferred for biomolecular simulations because it contains a virtual site and the forces must be projected on the "real" atoms. The mTIP3P water model has been selected since it reproduces the first shell hydration very well. In addition, most of the simulation time of solvated biomolecules is spent on simulating water molecules. Hence, a less costly mTIP3P model is favored .