Problems in Liquid Argon (Rahman, 1964) - Loosing Atoms


I’m trying to repeat the “experiment” done by Rahman in 1964 simulating Liquid Argon.

The parameters we (me and Rahman) used are:

units: metal
T = 94.4 K
epsilon = 0.010341 eV
sigma = 3.4 A
cut off = 7.65 A (= 2.25sigma)
mass = 39.95 g/mol
box size = 34.7786 A (=10.229
Number of atoms = 864

My input file is below.

In the first step i loose more than 300 atoms in my box. :frowning:

I can’t see what i’m doing wrong…

Thanx a lot

Raph Callef

You might be overlapping your atoms with the " create_ atoms random…". The documentation says:

IMPORTANT NOTE: The atoms generated by the random style will typically be highly overlapped which will cause many interatomic potentials to compute large energies and forces. Thus you should either perform an energy minimization or run dynamics with fix nve/limit to equilibrate such a system, before running normal dynamics.

Everything probably blew up since they were too close.

Could be wrong.

Mike Bifano
Ph.D. Candidate
Case Western Reserve University
Office (216) 368-6444
Cell (717) 926-8950

I'm trying to repeat the "experiment" done by Rahman in 1964 simulating Liquid Argon.

I am wondering if anyone can give me some instructions regarding
generation of nanocrystaline structure by Voronoi tesselation using
Lammps. or Do I need any other software to create polycrystal and
later on read by Lammps? Please enlighten me regarding this issue.
Look forward to hear from you soon.
Thanks in advance.
M. Rahman

Holy cow - two postings less than an hour apart. One about Rahman,
one from Rahman. What are the odds?

Could be different Rahman's I suppose ...