MAXSPECBOND parameter

LAMMPS LAMMPS Mailing List Mirror
1

Dear Sirs,

I am using the 17Dec13 lammps version and I would like to ask how to
increase the MAXSPECBOND, which should be in fix_reaxc_species.h, but
does not appear there. The message about the parameter is given after
crashes during equilibration of a system which used to run without
warnings on an earlier version.
Thank you,

2

Dear Sirs,

I am using the 17Dec13 lammps version and I would like to ask how to
increase the MAXSPECBOND, which should be in fix_reaxc_species.h, but
does not appear there. The message about the parameter is given after
crashes during equilibration of a system which used to run without
warnings on an earlier version.

a simple grep command would reveal that this parameter has been
consolidated into reaxc_defs.h so you should change it there.

not sure about why one version crashes and the other doesn't. quite
possibly the current version is more stringent in error checking and
the old one was doing out-of-bound accesses and thus would give
incorrect results, or you have a marginal case when some tiny
numerical differences do or do not result in triggering the message
and the abort. but ray shan is the authority on this and will likely
comment later.

3

It is difficult to tell without seeing and knowing anything. This
variable is the maximum number of bonds allowed on each atom and is
currently set to 24. This error is most likely to occur when the
dynamics is bad - meaning one or more atoms have more than 24 bonds.
Exam, analyze and visualize your system and see if anything obvious is
wrong. If not, please post a complete input deck.

Thanks,
Ray

4

Actually in my reaxc_defs.h the parameter MAXSPECBOND was 12. Now I
tried running a recompiled version with parameter set to 24 and
apparently there is something wrong with the species, which was not
there with the old version.
Thanks,

Osvalds

5

MAXSPECBOND should be 24 in reaxc_defs.h. I can run examples/reax
without a problem.

Update to the newest version, change MAXSPECBOND to 24, recompile and
try again. If it does not work, then your structure has bad dynamics.

Ray