[gmx-users] Constant Density

[Nash, Anthony]

Hi all,

At the risk of bending the rules of thermodynamics, I¹m wondering whether
Gromacs can maintain density of a water box (0.750 g/L density of water in
a collagen fibril environment) whilst applying an NPT ensemble?

gmx_d solvate, fills up to 2/3 of my truncated oct cell, with my protein
at the centre. An NVT simulation does not redistribute the water. To do
this I need to perform an NPT run, but even so this rapidly shrinks the
box. 

I have considering looking up the necessary pressure value for this
density, however I¹m a bit uncertain whether this maintains any
physiological realism for the protein itself.

I¹ve tried googling with little success.

Any thoughts are appreciated.
Thanks
Anthony