atomistic PRISM calculation, for determination of interaction parameter

[arashelahi]

Hi I am new user to pyPRISM and integral equation theory. thus my question may look simple, sorry about that in advance. I have the following questions. 1-I would like to assign an atom to each site in my monomer, rather than coarse-grained simulation, for doing that, what is the appropriate OMEGA and why? 2-In the examples that I saw and the referenced papers, solvent (in my case water) is simulated implicitly, can pyPRISM get explicit Solvent sites, because eventually, I would like to determine interaction parameter between the POLYMER and WATER, so I need at least two components. 3- In atomistic simulation, how interaction parameter between monomer and water can be determined? Is that an average of interaction between all atoms of monomer with water? or what is that?

The reason I would like to do atomistic simulation is, eventually I want to compare my results with experimental results(radial distribution) that is existing for atoms, rather than group of atoms thank you for your response