Problam:Providing the ITP file myself results in an error.

[kk-ssh]

Dear @hernanchavezthielemann I lost some force field parameters while using the autoload button. I tried to provide the force field parameters using the ITP file; however, since I only have one ITP file, I attempted to enter the required files for force field, non-bonded, and bonded as specified by the software. I encountered the following error: Dihedral potential problem found!! Adopting X-A1-A2-X configuration for: 1-2. Here is my itp file. Thank you for your assistance! 1.itp.json 3bon.itp.json 2nb.itp.json

[hernanchavezthielemann]

Dear Jing @kk-ssh,

Thank you for your question, try always with the autoload, that is fine, I think I should remove the other option at this point, since the autoload is kind of mature. I am not sure whether what you are getting there is an error, it looks to me like a warning (potential problem)

To better understand and check your error, I would need all your files ( .gro too) if those are all your itps, then I think you are missing the defaults directive this is an example of the defaults directive:

[ defaults ] ; nbfunc = 1 means to impose Lennard-Jones ; comb-rule = 3 means to provide sigma & epsilon ; fudgeQQ = 0.5 because we have electrostatic interacations ; nbfunc comb-rule gen-pairs fudgeLJ fudgeQQ 1 3 yes 0.5 0.5

you can find more about it in GROMACS manual, and bear in mind that the values are normaly given by the forcefield that you are using, so do not use something generic.

please let me know how it goes, Best, Hernan.