Hi all,

I am investigating the adsorption of organic molecules on a solid surface using MD calculation with FORCITE tool. The COMPASS force field is applied for organic molecules, and the interaction between them with the solid surface is decribed by non-bond interaction using Lenard-Jones 9-6 formula. I want to derive the vdw parameters (epsilon & sigma0) for the interaction between them by fitting these parameters base on obtained adsorption energy and structure from ab initio calculations from Dmol3.

Can anybody show how to do that ?