beginners question nvt integegration

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1

Dear LAMMPS users and devs,

a short beginners question:

If I set up integration with:

fix integrator all nvt temp 3.0 3.0 0.5

can I than check quality of simulation with

variable cq equal etotal+f_integrator/atoms

as it is the conserved quantity mentioned in the papers for nhc integration?

Best,

Norman

2

See the fix_nh.html doc page for info on this.

E.g.

The “fix_modify”_fix_modify.html {energy} option is supported by these
fixes to add the energy change induced by Nose/Hoover thermostatting
and barostatting to the system’s potential energy as part of
“thermodynamic output”_thermo_style.html.

Steve

3

Thanks for the quick answer.

Is this equivalent to what I used to do?
What if I want to look at the potential energy of the physical system alone?

Is it better to use
"variable cq equal etotal+f_integrator/atoms"
without "fix_modify integrator energy yes"

or
"variable pephys equal pe-f_integrator/atoms"
with "fix_modify integrator energy yes"

I normally use the potential energy to see if the system has reached
equilibrium, since it seems to relax slower to it's equilibrium value
than other quantities.

Thanks again.

4

I don’t know what’s “better” for what

you are looking for. I suggest you experiement
with the different options and examine the output.

Steve