Dear All,
Hi
I have three atom types in my model and 2 terosoff potential files, the first one makes bond between atom type 1 & 2 and the second tersoff file makes bond between atom type 2&3. Do you know how can I use pair-coeff in LAMMPS to simulate this model? Should I use hybrid command? Please let me know if you have any example for this problem.
Sincerely,
Dear All,
HiI have three atom types in my model and 2 terosoff potential files, the
first one makes bond between atom type 1 & 2 and the second tersoff file
makes bond between atom type 2&3. Do you know how can I use pair-coeff in
LAMMPS to simulate this model? Should I use hybrid command? Please let me
no, you cannot use a hybrid model, since you have manybody potentials
and not pairwise additive potentials.
you would have to build a potential file that has parameters for all.
please note that due to the manybody nature of tersoff, you need not
only interactions between all pairs of two atom types, but also for
all *triples* of atom types.
know if you have any example for this problem.
this topic has been discussed *many* times on this very mailing list.
please look through the mailing list archives for the previous
discussions and learn what you need to know from them.
axel.
Thanks for your answer. Actually, it is very hard to make all manybody bonds in one single file. Is there any alternative to join these two files? using table command or other methods?
Thanks,
Thanks for your answer. Actually, it is very hard to make all manybody bonds
in one single file. Is there any alternative to join these two files?
none i know.
using table command or other methods?
again, tabulation is for pairwise additive potentials, but you have
manybody potentials.
axel
Do you know any other potential or any other determined way except tersoff to simulate C-N-H bond?
Do you know any other potential or any other determined way except tersoff
to simulate C-N-H bond?
this is a question that cannot be answered in this generality unless
you use a quantum mechanical model.
classical potentials are always parameterized for certain families of
compounds under certain conditions. on top of that, different types of
classical potentials can be used for the same kind of compound, but
with different levels of accuracy and transferability.
the best way to find what is the right set of potentials is to search
the published literature and see what others have chosen for the same
or similar compounds and then make some tests to determine which of
the choices is best for your case.
axel.