Dear LAMMPS users,
I have a question about the fix ttm command. The manual says this command requires periodic boundary conditions. Supposing I have a metal block in contact with a non-metal block and I apply “fix ttm” only to the metal side, how will the periodic boundaries work? Will the temperature of electrons at the two ends of the metal be identical?
Regards,
Kira Banks
Dear LAMMPS users,
I have a question about the fix ttm command. The manual says this command
requires periodic boundary conditions. Supposing I have a metal block in
contact with a non-metal block and I apply "fix ttm" only to the metal side,
how will the periodic boundaries work? Will the temperature of electrons at
the two ends of the metal be identical?
you should read the referenced publications about the method.
it seems from the comment that the restrictions to PBC and
an orthogonal box are primarily due to the way how the grid
is defined for the electrons.
if you need more flexibility, you may want to check out the
AtC package instead.
cheers,
axel.
Paul can comment further.
Steve
I have a question about the fix ttm command. The manual says this
command requires periodic boundary conditions. Supposing I have a
metal block in contact with a non-metal block and I apply "fix ttm"
only to the metal side, how will the periodic boundaries work? Will
the temperature of electrons at the two ends of the metal be identical?
The way "fix ttm" is currently written, the electron mesh will encompass the entire simulation domain, both the metal and non-metal, so it is impossible to apply fix ttm to only the metal side. The electron temperatures at opposite ends of the box will be forced to match due to the periodic boundary conditions.
Sounds like you'll need to pick one of the following:
1) model periodically repeating slabs of metal/non-metal
2) modify fix ttm to meet your needs
3) use another software option, such as the AtC package as Axel suggested.
Paul
Dear Alex, Steve and Paul,
Thanks for all your comments.
Bests,
Kira