[gmx-users] Topol file for a bigger system

[Alex]

Dear all,

Using topolbuild I can generate the case.gro, case.top, ffcase.itp and
posrecase.itp out of a case.mol2 which contain only a single molecule of X.

Also, using the "gmx insert-molecules" I can generate a bigger system
containing 1000 molecule of X, for example to have case-1000.gro.

Now, I was wondering how I can update the case.top and itp files for the
new system? I am trying the "gmx x2top" but first of all it is really time
consuming and also at the end it can not find the force fields for some of
the atoms.
(~> gmx x2top -f case-1000.gro -o out.top -r out.rtp)

Any help would be highly appreciated.

Regards,
Alex