Pressure is not going to 1 bar

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Dear Gromacs users
I am doing a protein-ligand simulation in which I was getting Lincs warning during the production run. To solve this I run longer energy minimizations and after nvt; I run npt in 2 steps first 500 ps at Berendsen and second 500ps at Parinello-Rahman
I am getting following values for pressure for the first equilibration:-

Energy Average Err.Est. RMSD Tot-Drift

Pressure -3.41278 3.7 73.0311 22.1736 (bar)

Statistics over 500001 steps [ 0.0000 through 500.0000 ps ], 1 data sets
All statistics are over 5001 points

For the second npt

Energy Average Err.Est. RMSD Tot-Drift

Pressure 0.702052 0.32 68.0829 0.180525 (bar)

The pressure did not reach to 1 bar yet. Should I run longer npt or it is sufficient for starting production run?
I need your valuable suggestions, please. I have attached npt.mdp files for your review and suggestions.
npt2.mdp (2.6 KB) npt.mdp (2.6 KB)

Hi sadaf,

The pressure can vary quite drastically during simulations, especially when you run a quite small system. On first sight, your .mdp file looks okay.

This topic gets discussed frequently, including within the last few days on this forum. Please refer to and ask yourself: is 0.7 ± 68 statistically different from the target value of 1?

Some examples to show you how much pressure can fluctuate, and how it is a factor of the number of atoms/particles in the simulation: