Thermostat regions in MD

[Philippe C. A.]

On Aug 9, 2:14 pm, Teodoro Laino <teodor... at gmail.com> wrote:
> This is not possible. The region section is only specifying an ensemble of atoms in which the temperature is kept under control.

This is exactly what I want. I want to specify an ensemble of atoms
(say atoms 1 - 250) whose temperature is kept under control by the
thermostat, and the atoms outside of that ensemble are unaffected by
the thermostat.
How do I do that for the Nose-Hoover thermostat? The input file
section from my previous post apparently is wrong.

> > &MOTION
> > &MD
> >  ENSEMBLE NVT
> >  TEMPERATURE [K] 500.0
> >  &THERMOSTAT
> >   TYPE NOSE
> >   REGION DEFINED
> >   &DEFINE_REGION
> >    LIST 1 2 3 [...] 250   # My system has 250 particles A and 250
> > particles B
> >   &END DEFINE_REGION
> >   &NOSE
> >    LENGTH 1
> >    TIMECON [fs] 1.0e-2
> >   &END NOSE
> >  &END THERMOSTAT
> >  TIMESTEP [fs] 1.0 fs
> >  STEPS 20
> > &END MD
> > &END MOTION