[gmx-users] ligpargen

[farial tavakoli]

Dear GROMACS users
I am trying to run an md simulation on my protein in complex to a small molecule, using OPLSAA force field. then I am going to calculate binding energy using G_MMPBSA, G_MMPBSA is not able to calculate the binding energy with CHARMM36 force field, so I have to use OPLSAA. 
which one of topolbuild, topolgen and ligpargen programs is advised to generate topology for my small molecule?
best regards
Farial