create_atoms region style

Using create_atoms region style command , a region is defined whose volume can be different from simulation box volume. The volume and hence density of simulation box can be easily known . But how to determine the volume (and hence density) for the region defined to create atoms.

well, if its a simple region like a sphere, you can compute the volume
yourself. If you use a lattice command to put atoms into
a region, you are effectively defining the density. The create_atoms
command will simply fill the volume (whatever shape it is) with
atoms at that density. You don’t have the freedom to choose N = #
of particles in an odd shaped volume.

Steve

Thanks Steve for your comments.
If I use Thermo_style density, it computes density of the entire simulation box. I just want the density at every timestep of the region where I have put the atoms initially as my entire simulation box is not filled with atoms.

Thanks Steve for your comments.
If I use Thermo_style density, it computes density of the entire simulation
box. I just want the density at every timestep of the region where I have
put the atoms initially as my entire simulation box is not filled with
atoms.

since LAMMPS cannot read your mind, all pre-defined computations are
set up for the most common or more easily computed property.
if you want custom information, you'll have to use a custom
computation to generate the information you want. this is easily
possible using equal style variables.

axel.