L-J and electrostatic force

I’m evaluating the interaction between two membranes. From shearing tests, I know the membrane-membrane interaction have qualitative difference for two different configurations and I am trying to make quantitative comparison by using metric such as force or energy, so if I can obtain either of these two quantities, it will give me some start on the analysis.

There are some water molecules between the membranes but the mean head group to head group distance across water is somewhere from 0.7-1.2 nm. This is why I believe electrostatic or the vdw are relevant. In addition, at this length scale, water cannot be treated straightforwardly as a continuum. In any case, as you said, by taking account of the dielectric constant, we can acknowledge the lower limit of the interaction (force or energy). Therefore I don’t think it’s overall useless.