pair_style lj/sdk/soft and pair_style lj/sdk/coul/long/soft

Dear Users,

I am performing coarse-grained MD simulations to calculate solvation free energy of a drug molecule in electrolyte solution.

I am using SPICA force field.

So, I need to decouple the drug-solvent interaction by using pair style lj/sdk/coul/long/soft. This pair style is not implemented in LAMMPS code.

I added these soft potentials (lj/sdk/soft and lj/sdk/coul/long/soft ) in the LAMMPS code and installed successfully.

After that, I ran coarse-grained simulation of water by using pair style lj/sdk.

I tagged one water molecule by T. So, I can calculate hydration free energy of water.

Solvation free energy simulations:

Parameter file is

The /soft potentials are part of the USER-FEP package and contributed/maintained by external developers.
Please see the README in the src/USER-FEP folder for the authors and contact them for assistance with implementing the soft core variants that you are looking for.