Generating topology from gmx x2top

User discussions
1

GROMACS version:2021.4
GROMACS modification: Yes/No
Here post your question
I have a protein with a metal ion. After the running Acpype, the input topology used to run MD in GROMACS doesn’t work. So, I am trying to generate a new topology file using gmx x2top. I get an error saying:
Fatal error:
No or incorrect atomname2type.n2t file found (looking for amber99sb.ff)
I want to use amber99sb forcefield.

2

For AMBER99SB use CHARMM-GUI.