AtC for indentation and "fix_modify atc fix displacement" issues


Dear LAMMPS developers and users,

  1. I have modified an ATC example “in. in.eam_unistrain_cell” under \examples\USER\atc\hardy to include indentation. I have attached the modified input file. The simulation results are not as expected, because the MD region was deformed even when the indenter is still far away. And then the simulation ended with the following message: “ERROR: Lost atoms: original 83232 current 83156 (…/thermo.cpp:442)”.

  2. I tried to set the boundary conditions in an “atc hardy” case but the “fix_modify AtC fix displacement” doesn’t work and I got an ERROR: Illegal fix_modify command (…/fix.cpp:155). However, in the LAMMPS examples for “atc elastic”, e.g., \USER\atc\elastic\in.bar1d, commands such as “fix_modify AtC fix displacement x lbc 0” did work.

Does anybody know why this happens? Does “fix_modify AtC fix displacement” only work for “atc elastic” cases? It seems that the indent fix is not compatible with AtC or with the NVT ensemble. I will appreciate any suggestions.


Yuqing Ding

Canadian Nuclear Laboratories

in.eam_unistrain_cell (2.75 KB)

I think you need to confer with the USER-ATC package authors on these Qs.
They are listed in the src/USER-ATC/README file with email addresses.