[gmx-users] Box was shifted at least 10 times

[Sheikh Imamul Hossain]

Hi all,
I am running a simulation of a system contains DPPC (716) and POPG (307)
lipid monolayer with CG AuNPs. In my system, I have added the counter ions
to neutralize the system and added also 0.15 M NACL (NA-136, CL-136) into
my system. After minimization, I run 6ns equilibration (Time step was15 fs)
with V-rescale thermostat and Surface tension scheme has been applied in
Berendsen pressure coupling with 4.5 ×〖10〗^5 bar-1 compressibility in the
xy plane. To fix the box height constant along z-axis, the compressibility
has set to 0 bar-1. Time constant for pressure coupling was 8ps. Everything
was okay. But when I run second equilibration for 10ns with time step 20fs
the I got the error "Box was shifted at least 10 times and  pressure
coupling is more than 1%". I didn't nothing but only changed equilibration
time 6ns to 10ns and time step 15fs to 20fs.

N.B. There was no such problem when the system doesn't contains additional
salt concentration with having  same above mentioned parameters.

How can I solve this problem?

Thanks in Advance
Imamul

Sincerely Your’s
*Sheikh Imamul Hossain*
PhD Research Student