lammps-users Digest, Vol 92, Issue 68

Dear all,

I want to set the left part and the right part of my simulation box into two different colour, but my system is pure system and it only contains one element. How can I do this in lammps.
I used the command “set”
“set group left type 1;set group right type 2”, in this case, I have to set 2 type of atoms in my simulation “create_box 2 box”, if I set “create_box 1 box” and it did not work. But if I set two type of atoms in the input file, I have to provide 2 type of potentials but my system is pure system and there is only one element in my simulation. I also have tried to set two types atoms in the potential, they both have the same potential parameters regardless that they are different in terms of the name, but this did not work in the MEAM potential as well. Is there any command can do this ?



If you want to have 2 types of atoms, you have to use
create_box 2 - that should be obvious.

The MEAM (and all other potentails in LAMMPS) can

be setup to apply the same parameters (for a physcial element)
to multiple atom types. See its doc page.