Replica-exchange ABF

LAMMPS LAMMPS Mailing List Mirror
1

Dear LAMMPS Users

I wish to run replica-exchange ABF with both “temper” and “fix colvars” commands. Is it possible? If so, as for output files from fix colvars, e.g. the default “out.colvars.traj”, does it refer to one particular replica, or it is a synchronized communication between all replicas updated at intervals?
I apologise if my question is not very clear. It is just that in the colvars user manual, there seems only information for multi-replica metadynamics.

Best Regards

Lunna

2

Hi Lunna, can you clarify what is the exchange criterion that you would like to use? I’m copying Jeff Comer, who authored the multiple-replicas ABF paper, and can answer more completely.

For additional methods based on replica-exchange + metadynamics (for which a massive amount of work has been published) you could also try Plumed, which has become a lot easier to build with LAMMPS in the current release.

In the specific case of multiple-replicas metadynamics every output file produced by fix colvars only contains directly information for that replica. If you run 10 replicas, those would be 10 different simulations, which will need different output prefixes.

Giacomo

3

Hi Giacomo

Thank you very much.

What is the exchange criterion that you would like to use?

  • I wish to run replica exchange at a few different temperatures with only one reaction coordinate e.g. distance defined in the colvars file as read in by “fix colvars”
    At the moment I cannot find how to make every “fix colvars” output only containing information for that replica.

At the moment, I have not tried replica-exchange + metadynamics as well as Plumed yet due to my slow progress with the colvars module, but thanks a lot for the detailed recommendations! I will also start to look at this combination.

Best Regards
Lunna