Dear Lammps Users,
In the Reax examples, I find that the charge column of all the data files is 0. And in the input files, the command fix qeq/reax is all used. So I am very confused about this. Theoretically, is it necessary to define the charge value of every single atom in order to perform the charge equilibration? Thanks in advance.
QEq will overwrite all charges at each time step, so defining them in advance has no impact on the simulation.
Kristof
Hi Kristof,
Thank you very much for your reply.
If it is the case, does it mean that the results will be the same whether I define the charge value of all the atoms or leave them all 0 in the data file, which means the initial charge value of the atoms doesn’t matter at all?
Kind Regards,
Lance
Hi Kristof,
Thank you very much for your reply.
If it is the case, does it mean that the results will be the same whether I
define the charge value of all the atoms or leave them all 0 in the data
file, which means the initial charge value of the atoms doesn't matter at
all?
the initial charge values will be used as starting point for the
charge equilibration, thus they can be used to "guide" the system
toward the right state.
most of the time, it shouldn't matter, except for tricky cases, and
even in those cases, the situation should be rectified during the MD
run sooner or later.
axel.
Hi Axel,
I understand now. Thank you very much for your help!
Lance