CHARMM Development Project Forums User Discussion & Questions Performance and Benchmarking kunit together with openmm

Hi, just want a confirmation that kunit does not work well with openmm. In my script it works well without openmm. However, with openmm it prints nothing to the kunit file. Can anyone confirm it? Thanks.

Confirmed. OpenMM does not return the individual energy terms to the main program. See openmm.doc:
"WARNING: At present the energy file is not written, since OpenMM only returns the total energies
(TOTE, TOTKE, EPOT and TEMP) and VOLUME."

If you absolutely need some specific energy terms you can post-process the trajectory using the energy command inside a CHARMM loop with the TRAJ READ command (dynamc.doc); something like this
TRAJ ...
label loop
traj read
energy/interaction_energy
echo energy terms
goto loop