I am using charmm36 forcefield for protein-ligand simulation. While trying to add ions to the solvate I’m getting
Error: in lig.prm
unknown bond_atomtype OGTIP3
I’m using the latest forcefield file and latest updated version of gromacs.
Kindly help me with this error.
Thank you!
Whatever you uploaded to the CGenFF server has water in it, because OGTIP3 and HGTIP3 are the O and H of TIP3P water. We don’t support this in GROMACS because those atom types are not standard parts of the force field.
Upload the molecule of interest without water to generate its topology. There is no need to try to generate topologies for water, which are well represented by existing models.
Thank you so much for the response
Was very helpful