[gmx-users] .itp and .rtp file modifications?

[Elie M]

Dear all,
I am trying to minimize the energy of a polymer system I have. I have successfully modified the n2t file to include force fields for atoms that were not present. However now I am using "grompp" before using mdrun (to minimize). However I have a question should the .ITP and .RTP files be modified accordingly and if yes how is this possible? Any information of how to modify them? 

Elie