[lammps-users] Lost Atoms

I’m new to lammps, and I tried to modify the friction example in order to just create a 3-D solid surface. However, I’m got a “lost atoms” error.

Input script and error message follow below.
very respectfully,

3d hydrophobic substrate simulation

dimension 3
boundary f f f

atom_style atomic
neighbor 0.3 bin
neigh_modify delay 5

create geometry

lattice fcc 0.9
region box block 0 50 0 22 -0.25 0.25
create_box 1 box

mass 1 1.0

atom regions

region substrate block EDGE EDGE EDGE EDGE EDGE EDGE

create 3d surface

create_atoms 1 region substrate

LJ potentials

pair_style lj/cut 2.5
pair_coeff * * 1.0 1.0 2.5

define groups

group slab region substrate

set group slab type 1

initial velocities

compute new slab temp/region substrate
velocity slab create 0.1 482748 temp new


fix 1 all nve


timestep 0.0025
thermo 1000
thermo_modify temp new

dump 1 all atom 500 dump.3dsubstrate
run 20000

You need to figure out why you are losing atoms, likely due
to big forces blowing them out of the box. Viz and dump files
and lots of thermo output should help you find what's going
wrong in your model.