[gmx-users] Anisotropic Pressure Coupling

[Adriaan Riet]

Hello,

I've been trying to run a simulation using anisotropic pressure coupling (I
want to allow the box to adjust to the right size for a zero-pressure
simulation). I am using the following settings in the .mdp file:

    Pcoupl               =  Berendsen
    pcoupltype           =  anisotropic
    tau_p                =  2.0
    compressibility      =  4.5e-05 4.5e-05 4.5e-05 0 0 0
    ref_p                =  0 0 0 0 0 0

I can grompp the mdp file without error, but when I try to execute mdrun on
the tpr file, I obtain the following message:

Fatal error:
Domain decomposition has not been implemented for box vectors that have
non-zero components in directions that do not use domain decomposition:
ncells
= 1 8 1, box vector[2] = -nan -nan 0.000000

If I change the pressure coupling to isotropic and delete the spare matrix
components from the settings, the simulation runs without error.

Am I not properly specifying the parameters? Is there another error that I
could be missing?

Thank you,
Adriaan