Some problem with Tersoff and REBO potential

hi, all

I tested running a simple simulation with a small block of diamond using
Tersoff and REBO potentials. The block shows a melting behavior at a low
temperature of about 300 K, which seems abnormal. I wonder whether there
is something wrong with the code, if it's not because of my stupidity.
My simple example using Tersoff potential is attached with this email.
Please check it. The pbc is actually exerted on the z axis with a big
box length for the xy axes. The lammps version I used is 31Oct10.

Best regards,

Wei Zhang

input.lammps (19.2 KB)

in.MD (308 Bytes)

Dear Zhang,

For the Tersoff potential use the unit “metal” rather than real. Please read the documentation here: http://lammps.sandia.gov/doc/pair_tersoff.html and http://lammps.sandia.gov/doc/pair_airebo.html.
You should check again your input data of atoms coordinate also, maybe it is not correct, because when I tried to run your simulation, it seems that your crystal explode.

Cheers,
rizal

2011/4/19 Zhang Wei <zhangweiwww@…24…>

Dear Rizal,

It’s just because I used the wrong units. Thank you very much.

Best regards,

Wei Zhang