Subject: Parallelizing fix sgcmc with MTP in LAMMPS for Hybrid MD/MC simulation

Hi everyone,

I am currently working with LAMMPS (version 22DEC2022) to conduct hybrid MD/MC simulations on a 5-element high entropy alloy system using Moment Tensor Potentials (MTP). I’ve built LAMMPS with the MC package and the USER-MLIP package necessary for MTP.

However, I’ve encountered a error when attempting to run simulations across multiple processors. The error message I receive is: ‘ERROR: Cannot run fix vcsgc with naive total energy calculation and more than one MPI process. (…/fix_sgcmc.cpp:251)’. Running the calculation on a single processor is possible but extremely time-consuming, taking over two days to complete just one timestep.

Could anyone advise on how I might parallelize the fix sgcmc process while using MTP forcefield?

Thank you

This is significantly outdated. If you want to do code development, you should be using the latest feature release 7 Feb 2024 or use the “develop” branch of the git repository.

Please have a look at the two functions of the fix: FixSemiGrandCanonicalMC::computeEnergyChangeEAM() and FixSemiGrandCanonicalMC::computeEnergyChangeGeneric()

To run in parallel with multiple MPI ranks, you would have to add a function that works similar to the former and produces the same results as the latter.