Warning message saying "Warning: changed valency_val to valency_boc for 1

Dear LAMMPS users,

I have just started studying ReaxFF in Lammps. When I run simulation of methane molecules using the ReaxFF, several warning

messages occurred saying "Warning: changed valency_cal to valency_boc for

1". And, at the end of test.lammps file, I saw ‘srun: error: nid00083: tasks 32-63: Segmentation fault’. I wonder what these warning messages means and how I can solve these problems.

Many Thanks,


This is a warning message generated by the section of code that performs some consistency checks on the ReaxFF parameter file. I have never before seen it actually trigger a warning, which suggests that either you are using a very unusual ReaxFF parameterization (not one that comes with LAMMPS), or your parameter file has somehow been corrupted. I suspect the latter, as the element type is listed as “1” in your warning message. I suggest you start your work using a standard ReaxFF parameter file (see examples/reax), with a small system, running on just 1 or a few cores.


I’m also getting these warnings although I am using reaxff files provided with AB in lammps examples.