Two different regimes contribute to the overall membrane pressure profile behavior in Fig. . The first is the outwards repulsive contribution of the hydrophobic chains due to the steric interactions. This increase in the lateral pressure profile is due to the interdigitation of the two leaflets. This contribution can been seen in Fig. as positive values for the lateral pressure profile around -18 to +18 Å. This increase has been measured computationally and experimentally 73 on different membranes. The second is the decrease in the lateral pressure due to the interface between lipid head groups and tails, leading to the sharp dips around -20 and +20 Å in Fig. . This decrease has been previously reported experimentally and computationally this dip has been seen to be proportional to the amount of unsaturation in the membrane. Previous computational studies have reported a different pressure profile pattern at the interface. Membrane systems which lack any unsaturation have dips around -500 to -1000 bar. Having one unsaturation site makes the pressure profile dip below -1000 bar, similar to what we observe in our simulations.