Question about file output in replica exchange simulations using the temper command in LAMMPS

Dear LAMMPS Users,

I have a questions concerning the temper command that is used to run
replica exchange simulations in LAMMPS.

According to the documentation, replicas are assigned to different
processor groups based on the partition command, and the temperatures
are exchanged between replicas (as opposed to the atomic coordinates).
  I have read that separate outputs may be specified for each of the
replicas, which means that the temperature varies over the course of
the simulations for each of these output files (if my understanding is
correct).

I am looking to obtain configurations over the course of the
simulations that are at constant temperature. For example, if I have
3 replicas running using temperatures of 275, 300 and 325 K, I would
like to get a DCD (or xyz) dump that contains only the coordinates
corresponding to the replica at 300 K. Is there a way to do this
directly in LAMMPS?

Thanks for the help!

Kind Regards,
Jeremy Palmer

Graduate Student
North Carolina State University

Dear LAMMPS Users,

I have a questions concerning the temper command that is used to run
replica exchange simulations in LAMMPS.

According to the documentation, replicas are assigned to different
processor groups based on the partition command, and the temperatures
are exchanged between replicas (as opposed to the atomic coordinates).
I have read that separate outputs may be specified for each of the
replicas, which means that the temperature varies over the course of
the simulations for each of these output files (if my understanding is
correct).

I am looking to obtain configurations over the course of the
simulations that are at constant temperature. For example, if I have
3 replicas running using temperatures of 275, 300 and 325 K, I would
like to get a DCD (or xyz) dump that contains only the coordinates
corresponding to the replica at 300 K. Is there a way to do this
directly in LAMMPS?

no.

axel.

You do realize that there is no one replica that is at 300K?
Rather there is always some replica that is at 300K at each
stage, but which one it is swaps from time to time. Thus
it is not a continuous trajectory.

That said, the Pizza.py tool can be used to post-process
as set of dump files and create a new one from pieces
of the others.

Steve