[lammps-users] Building cylinder porous

Dear lammps users,

I want to build this kind of system:

one cylinder nano channel (not CNT, but much simple one)and gas molecules permeate through, only need LJ612 potential.

as i thought, it maybe the following step for construct the system before decide ensemble, temperature control,etc.
1 build a simulation box
2 build a cylinder channel with A type of molecules and upstream initialization of B type molecules
3 define A and B type molecule property with known values so that they are wall and gas molecules

but I am not sure is it right or not, building this geometry, as some errors occurs when create box and boundary, still, how to keep wall molecules at their region in order to perform that they are “fixed” surface is a question for me, previous instance is add spring-like force between them.

thank you all


LAMMPS does not have sophisticated "builder" commands.
Most people create their own geometries as a pre-processing
step, either by writing their own program to do it, or by
using another MD program that has a builder, writing out
a config file, and converting it to LAMMPS format. For the
conversion step, LAMMPS has several tools in its tools dir.

If your system is atomic (not molecules with bonds), then
the region and create_atoms and lattice command, enable
you to build reasonably complex geometries. If you want
molecules with bonds (e.g. water molecules), then you need
to do what I suggested first.