strain diffusion

Dear Lammps users,

I am trying to study the effect of stress on hydrogen atom in Zr. I am doing it in 3 steps . minimizing structure , calculating MSD at const volume , deforming it and then calculating MSD at constant volume by using the following script. But I cannot see any movement of hydrogens after deformation of Zirconium?.Can you tell if I made any mistake in script?

units metal
boundary p p p
atom_style atomic
pair_style meam
lattice hcp 3.232
region box block 0 10 0 10 0 10
create_box 2 box
create_atoms 1 box
create_atoms 2 random 10 878567 box

group zr type 1
group hydrogen type 2

pair_coeff * * meamf ZrN Hz ZrH2.meam ZrN Hz

neighbor 2 bin
neigh_modify delay 10 check yes

mass 1 91.224
mass 2 1.0079

fix 1 all nve/limit 0.1
minimize 1.00e-30 1.00e-30 100000 1000000
unfix 1

velocity all create 800.0 4928459 rot yes dist gaussian

fix 1 all nvt temp 800.0 800.0 100.0
fix 2 all temp/rescale 1 800.0 800.0 0.05 1.0

compute 1 hydrogen msd
compute 2 zr msd

thermo 1000
thermo_style custom step etotal ke temp pe press vol c_1[1] c_1[2] c_1[3] c_1[4] c_2[1] c_2[2] c_2[3] c_2[4]

run 4000000
unfix 1
unfix 2

thermo_style custom step lx ly lz press pxx pyy pzz pe temp
run 1

Store final cell length for strain calculations

variable tmp equal “lx”
variable L0 equal {tmp} print "Initial Length, L0: {L0}"

This is general advice for many people who
post to the list.

A complex script is like a computer program. It
has to be debugged, one line and one section
at a time, so you can be sure that the simulation
is doing what you ask and expect it to do. You can do
this by printing output, by visualization, by examining
dump files, by calculating values yourself by hand, etc.

No one is going to do this for you, for your model and
simulation. If you do this and have a specific Q
about a LAMMPS command or about why something
isn't working like you expect, then you may get
help from the mail list.