[gmx-users] Avg. Volume in NPT by Small Coupling Time

[Johnny Lu]

Hi.

How to get an accurate average volume for a system, such that the pressure
will be at 1 bar in a subsequent NVT run using this average volume?

Is it ok to use Berendsen barostat with a very small time constant (0.2 ps)
?
(At first I picked 0.1ps, gromacs 4.6.7 told me to use at least 0.2 ps).

I was hoping that a smaller time constant would allow the simulation to
sample the volume more frequently and Berendsen barostat would help the
system to converge to the correct average volume faster.

What are the possible draw backs?

So far (2 ns), I see that the pressure fluctuation is smaller than a PR
barostat.

It seems to be fine to use Berendsen barostat for this purpose ( [
https://mailman-1.sys.kth.se/pipermail/gromacs.org_gmx-users/2011-February/058453.html]
)

Thank you again.