[gmx-users] Constraint COM of water droplet at specific position with Umbrella sampling simulation

[Bui, Tai]

Hi all,

I am using Umbrella sampling to study the transportation of one water molecule from a droplet through  the membrane. I want to keep the water droplet at a specific position (X,Y,Z), and pull the water molecule. However I don't know how to keep the water droplet stay at one position with gromacs 5 (not using position restraint) (gromacs version 4 with pull-geometry=position can handle it).

Can anyone suggest the solution?

Thank you very much!

Kind regards,

Tai