[gmx-users] Negative Pressure during equilibration

[Sadaf Rani]

Dear Gromacs users

I am running a free energy test calculation and using position restraints
for all of the system. At the end of pressure equilibration I am
getting negative average pressure as below:-



Energy                      Average   Err.Est.       RMSD  Tot-Drift
-------------------------------------------------------------------------------
Pressure                  -0.292343        1.3    60.9244    8.84635  (bar)

I selected 1 bar ref pressure. Why is it going negative how should I fix
it? I need your kind suggestions.

Thanks in advance.

Sadaf