Potential reason for this could be use of TIPS3P water model, with surface tension of approximately 20 mN/m too low, in the parametrization of C36/LJ-PME lipid model. This underestimated water surface tension is balanced by monolayer tension when optimizing against experimental surface tension values, which leads to underestimated surface pressure values. Furthermore, the small monolayers used in the optimization may get trapped into local minima with a very di↵erent surface tensions from their equilibrium values because the formation of pores in prevented by finite size e↵ects. While the introduction of long-range van der Waals interactions in lipid bilayer and monolayer simulations is highly desirable, we conclude that the correct water surface tension is more critical to reproduce the experimental surface pressure-area isotherms and monolayer phase behaviour. On the other hand, increasing number of studies suggest that properties of water model are critical in many applications of MD simulations, such as studies of protein dynamics and conformational ensembles of disordered proteins. Therefore, using the state of the art water models during the systematic parametrization of force fields would most likely not only improve the description of monolayer behavior, but also facilitate other applications of MD simulations.