[lammps-users] setting different periodic lengths

Hi All:

I'm trying to set different periodic lengths in LAMMPS. My idea is to use the region command. For example, the following:

region box block 0 10.0 0 10.0 0 10.0 # set up a 10 x 10 x 10 periodic cell

would give a 10 x 10 x 10 periodic box of atoms. If I wanted to set a different periodic length in a given direction, would simply changing the length from 10 to something else do that, or is a different command necessary. Note that I don't want to move the periodic boundary dynamically during the simulation, I just want to see how the total energy of the system changes as a function of the periodic length.



Regions are just geometric domains. When you do "create box" you
set the simulation box to be a particular region you have specified.

So you can make that region any size you want (e.g. 10x15x22) and
it willl become the simulation box, filled with atoms once you
do create_atoms. See the lattice command for info on how to
fill the box with different kinds and lattices of atoms.

The boundary command determines whether the simulation
box is periodic or not.