[Lammps Users request] Help about msd

Hi all,

I have a question concerning the set of msd. I my project I ‘m trying to investigate
de diffusive behavior of BaTiO3 including oxygen vacancies in the temperature range
I was minimized the structure but when I try to run MD under PBC and nph ensemble
controlling the temperature with Berendsen Thermostat, to obtain msd of oxygen ion,
not diffuse. I believe that the problem is concerning to the pressure values, I want
to do it under atmospheric pressure (P=0GPa). I used the Virial correction to input
the pressure but nothing.
I did these simulations before by suing other software but LAMMPS is faster and I
want to learn.

Attached are two files: the minimization and equilibration and the dynamic input files:

Waiting for your help


units metal
dimension 3
atom_style charge
boundary p p p
atom_modify map array sort 0 10.0
neighbor 0.5 bin # I don't know if it is correct
neigh_modify delay 0 every 1 check no

lattice custom 16.04 a1 1 0 0 a2 0 1.0 0 a3 0 0 1 basis 0 0 0
read_data BT4x4x4.dat # 4x4x4 BaTiO3 unit cell

in.min (3.13 KB)

in.dyn (2.16 KB)