Revisiting the Lennard-Jones Implicit Solvent model for the Simulation of Dilute Polymer Solutions

Polymer chains in dilute solution usually exhibit different types of conformation and scaling behaviors based on solvent quality. In the Flory-Huggins theory, the conformation of a polymer chain in dilute solution can be directly connected to an excluded volume,ν, resulting in a universal scaling behavior and verifying the scaling behavior has been a subject of numerous experimental and computational studies. Different types of implicit solvent models have been developed to make simulations faster and to correlate the quality of solvent with excluded volume easier. In experiments, temperature is commonly used to control the quality of solvent. In the Lennard-Jones (LJ) implicit solvent model, temperature (T) or polymer-polymer interaction parameter (e_ij) or the LJ cutoff distance (r_c) can be independently varied to change the quality of solvent. The equivalency of these three approaches has never been tested through simulations, to the best of our knowledge, and will be the primary focus of this presentation.