Dear All,
I am having some doubts regarding the use of meam potential in LAMMPS.
I am planning to simulate a Silicon crystal substrate with Germanium and Gold adatoms.
So far, I can see meam potentials are better for Si & Au. I want use meam for all three atom types.
The meam potential parameters for Si & Au are mentioned in the library.meam file, whereas same for Ge is not there.
Shall I have to add it by hand from the reference paper.
For one atom system I can use the library.meam & NULL to get the potential parameters for the simulation.
For alloys (ex: SiAu) it is discouraged to use NULL, but the corresponding SiAu.meam file does not exist.
Does that mean I can create a SiAu.meam file to do the job?
When I have 3 atom types system, shall I have to have a SiAuGe.meam file?
Dear All,
I am having some doubts regarding the use of meam potential in LAMMPS.
I am planning to simulate a Silicon crystal substrate with Germanium and Gold adatoms.
So far, I can see meam potentials are better for Si & Au. I want use meam for all three atom types.
The meam potential parameters for Si & Au are mentioned in the library.meam file, whereas same for Ge is not there.
Shall I have to add it by hand from the reference paper.
For one atom system I can use the library.meam & NULL to get the potential parameters for the simulation.
For alloys (ex: SiAu) it is discouraged to use NULL, but the corresponding SiAu.meam file does not exist.
Does that mean I can create a SiAu.meam file to do the job?
When I have 3 atom types system, shall I have to have a SiAuGe.meam file?
You are really asking a MEAM question, not a LAMMPS question.
You are correct there are no Ge params in the library.meam file.
You would have to look in the literature to see if MEAM has been
used for Ge. If so then you can add the params to the file.
For an “alloy” system with several elements you only need an
additional file with additional params, if you think the default
MEAM mixing will not produce a good model. In the potentials
dir you can see several cases where people have tuned
the alloy params with extra files. Again you have to decide
from the literature if that is necessary for your SiGeAu system
(which it probably is). And you will have to create that
file in the format LAMMPS reads in.
Steve