[gmx-users] Tau_t error

[Mark Abraham]

Manik Mayur wrote:
> Hi,
> I am trying to remove thermostat on a certain group of atoms by taking 
> tau_t = 0. But upon using grompp it says:
> 
> "For proper thermostat integration tau_t (0) should be more than an 
> order of magnitude larger than delta_t."
> 
> And gives a warning. This was not there in v3.3. Is this a bug or should 
> I ignore it?

The proper way to remove temperature coupling is to modify tc_grps. See 
the equations in section 3.4.5 for a clue why a tau of zero might cause 
a problem.

Mark