I want to use the generalized replica exchange method on my system and I use the “temper/grem” command for this purpose!
The swap between adjacent ensembles when I use NPT simulation does not happen but when I change the NPT simulation to the NVT simulation this swap occurs!
Can you please let me know what can be the problem in this case?
I suggest you contact the author who is listed at the top of the src/REPLICA/temper_grem.cpp file.
Probably this implementation was not designed to work with NPT, only NVT. And it
needs to be extended.
There is also a temper/npt command if you want to try it.
Thanks for your reply.
The temper/grem command works with
the NPT simulations when the pair_style is “lj/cut”
but when I use TIP4P water model pair_style, it does not show any swap between replicas!
On the other hand in LAMMPS documentation no restriction is mentioned about this fix command!
If you mean a note in the doc page for temper/grem, then I don’t think it’s an issue with the command.
If a tempering method makes no swaps it is typically b/c there is not sufficient
overlap in the adjacent temperature states to “accept” the swap. That may be a function
of the model. But that is up to you as the user of a tempering command to figure out.
It’s typically not something the tempering method is smart enough to figure out. As least
not for the implementations in LAMMPS.