[gmx-users] Position restraint on flexible models of water

[Justin Lemkul]

On 1/13/18 4:44 PM, Iman Ahmadabadi wrote:
> Dear Gromacs users,
>
> As you know, there is a position restraint for water molecules (on each
> oxygen atom) in the topology file. what is purpose of this restraint in the
> topology files?
>
> My second question is: this position restraint should exist while I'm using
> a flexible model of water or not?

Position restraints are always optional, controlled by .mdp keywords. 
They're present in all topologies in the event that they're needed. 
Restraining water would be very uncommon.

-Justin

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Justin A. Lemkul, Ph.D.
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