[gmx-users] FEP with energy group exclusions

[Maik Goette]

Dear all

I am using FEP(TI) with energy group exclusions, to exclude interaction 
between the first molecule (B-State, fully dummy) and the second one 
(A-State, becomes dummy).
g_energy yields 0 energies between them and that is fine.
But for some reason, I switched the energy groups exclusions off. 
Because there are 2 atoms (one real, one dummy) directly on top of each 
other, I expected the system to instantly crash...but it run through the 
whole sim!
Now, g_energy yields again 0 between the two groups...though energy 
group exclusion is off. Is this a bug, or am I missing something?
The topology is correct, the index-file, too (as far as one can 
perfectly check them manually;) ).

Regards

-- 
Maik Goette, Dipl. Biol.
Max Planck Institute for Biophysical Chemistry
Theoretical & computational biophysics department
Am Fassberg 11
37077 Goettingen
Germany
Tel.  : ++49 551 201 2310
Fax   : ++49 551 201 2302
Email : mgoette[at]mpi-bpc.mpg.de
         mgoette2[at]gwdg.de
WWW   : http://www.mpibpc.gwdg.de/groups/grubmueller/