invalid atom type in create_atoms command

Dear LAMMPS users,

Hi, I wanted to generate two types of atoms in my system, so that it’s easier for visualization easier.

After setting up the region and lattice etc like

units

atom_style
lattice

region sheet block -3 3 -3 3 6 6.5
boundary p p p

create_box

create_atoms 1 region sheet

here’s the problem

“ create_atoms 2 single 0 0 0”

LAMMPS can’t generate the single atom of type 2; however, if I changed it to

“create_atoms 1 single 0 0 0”

There won’t be any error message.

What should I do to ensure that atom type 2 is valid?

Thanks,

Andy

The create_box command has a maxtypes arg that
is the maximum # of atom types your simulation will use.

Steve