[gmx-users] oscillations in pressure (NPT)

[Valentin Gogonea]

Dear Gromacs users,

I tried to run a NPT simulation (100 ps) of one of the demo examples 
that come with gromacs distribution (cpeptide in share/tutor/gmxdemo/). 
I got large oscillations of the pressure, I searched the mailing list 
and following the suggestions given in an earlier discussion I 
increased the tau_p from 0.5 to 2.0 and than 5.0 without success.

I used the Berendsen barostat (I included the md.mdp file)

I would appreciate if anybody can provide some advice of what to do to 
remove these pressure oscillations. I included here the pres.xvg files 
obtained with the g_energy program for the three simulations.

Thank you.

Valentin

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