GROMACS version: 2021.2
GROMACS modification: Yes, brew on Mac
My question is about the pcoupl. I intend to have the NpT ensemble, but need to fix one direction, for example, allowing the pressure coupling only in x and z but fix the box length in y.
The manual suggests the anisotropic
pcoupltype, so currently I have my .mdp with the following lines:
pcoupl = Parrinello-Rahman
pcoupltype = anisotropic
tau_p = 5.0
ref_p = 1.0 1.0 1.0 0.0 0.0 0.0
compressibility = 4.5e-5 4.5e-5 4.5e-5 4.5e-5 4.5e-5 4.5e-5
My question is how to fix the y direction? Change the compressibility of y to a much higher value? It seems a rare case but I hope to avoid any fluctuation by the barostat in the y direction.
Thank you in advance.