Many-body heat flux correction about python-ace HOT 2 OPEN

Hi @rfhari , thank you for using PACE!

We explicitly provide "pair" forces for each atom to LAMMPS (https://github.com/lammps/lammps/blob/develop/src/ML-PACE/pair_pace.cpp#L223) so, I would assume that atomic virials also should be computed by LAMMPS correctly.

Please, check it and let us know if it work.

Regards,
Yury

from python-ace.

I think ACE does not have the required 9-component per-atom virial for correctly calculating the heat flux yet.

In terms of code, one must use cvflag_atom in LAMMPS interface.

For theoretical background, one can check this review article that demonstrates how MTP (very similar to ACE) is failing to produce the correct heat flux: Molecular dynamics simulations of heat transport using machine-learned potentials: A mini-review and tutorial on GPUMD with neuroevolution potential. Therefore, it is not sufficient to provide pair forces for each atom to produce the correct atomic virials for heat flux calculation. More efforts are needed to make heat flux right.

from python-ace.