Error in adding Ions - ERROR 1 [file ffnonbonded.itp, line 56]

User discussions
1

GROMACS version: 2024.2
GROMACS modification: No

By using the GROMACS Tutorial for Protein-Ligand Complex, on the stage of adding ions in the molecule, the following coommand is excecuted:

gmx grompp -f ions.mdp -c solv.gro -p topol.top -o ions.tpr

But the following error appears:

ERROR 1 [file ffnonbonded.itp, line 56]:
Invalid function type 1 in push_at

How ca I fix this issue?

Best,
Suellen

2

As you see, there is an error in the ffnonbonded.itp file. That file is usually part of the standard force fields. What force field are you using? Have you modified this file?

3

I see, I really forgot to include the information about the force field. I am using the CHARMM36 force field in my studies.

4

Without any modifications? The ffnonbonded.itp of the official CHARMM36 download shouldn’t cause any problems. Could you post your topol.top file?