I am doing MD simulation for Protein-ligand docked complex using Gromacs 5.1.1. When I try to run the following command, I am getting the error " atom type O not found". I used OPLS all atoms force field.
gmx grompp -f ions.mdp -c solv.gro -p topol.top -o ions.tpr Fatal error: Atomtype O not found
How to solve this error? I am new to gromacs. Your suggestions would be appreciated! Thank you!