[gmx-users] proper tau_t value with SD

[Hyunjin Kim]

Hi,

Gromacs manual says that when "SD" used
as a thermostat, an appropriate value for "tau_t" is 2 ps, since this
results in a friction that is lower than the internal friction of water,
while it is high enough to remove excess heat (unless cut-off or
reaction-field electrostatics is used). However, the free energy tutorial
uses the smaller "tau_t" value, so I wonder whether I have to use 2 ps.

Thanks.

Hyunjin.