[gmx-users] topology file

[Andy Chao]

Hi,

I have a few technical questions regarding creating the topology file by
using the command "g_x2top".

I would like to use the following GROMACS's command:

g_x2top -f device.gro -ff oplsaa -o device.top

to convert the .gro file to .top.

The problem that I have is that the force field for carbon (graphene sheet)
and C4mimNTf2 are not defined.  Would you please let me know which file
must be modified in order to define the force field for carbon and the
elements in C4mimNTf2?

Thanks!

Andy