How to edit parameters in ffnonbonded.itp file in gromacs

GROMACS version:2022.4
GROMACS modification: Yes
I’m new to gromacs software.the non bonded parameters of research paper is different from ffbonded.itp file parameters for SCN to edit these.

You basically have to locate the folder containing the forcefield (if it’s one that included with gromacs, it should be in gromacs/share/top/), make a copy of it to include in your working directory, locate the ffbonded.itp file, add whatever parameters you need and use that forcefield. A good example to follow is the tutorial which includes instructions for adding the parameters of a lipid to a gromos forcefield (the exact details would of course depend on the forcefield your using and parameters you’re trying to add).

Thankyou so much,I will try this.