[gmx-users] grouping custom ions

[Alex]

Hi all,

Perhaps a trivial question here. I added a few custom metal ions into 
oplsaa's 'ions.itp' and 'ffnonbonded.itp' -- everything works fine. 
There is, however, a problem with selecting them in e.g. trjconv without 
using a custom index. Example: 5 NA, 6 CL, and 1 XX (custom) ions in the 
system. The group "Ion" now only contains 11 elements (NA + CL), while 
I'd like to select all 12 with "Ion". Things are scripted, so it would 
be really nice to be able to do that without additional indexing.

Thanks!

Alex