Dear Users,

I have performed molecular dynamics (MD) simulations of a polymer–solvent system and need to calculate the fractional free volume (FFV). I calculated the FFV for both the polymer–solvent system and the pure polymer system, obtaining values of 20% and 70%, respectively. The 70% value seems like an artifact to me. Could anyone clarify whether FFV should be calculated from the polymer–solvent system or the pure polymer in such simulations?

Thank you.

Hakkim