problems with “pair_style hybrid”

Dear all,

    I was trying to simulate the phase transformation of NiTiNb,now there are there potential files:NiTi.meam, NiNb.eam.fs, NbTiAl.eam.alloy.How to use them by the command "pair_style hybird"#atom type 1 Ni#atom type 2 Ti#atom type 3 Nbpair_style hybrid meam/c eam/fs eam/alloypair_coeff * * library.meam Ni Ti NiTi.eam Ni Ti Nullpair_coeff 1 3 eam/fs NiNb.eam.fs Ni NULL Nbpari_coeff 2 3 eam/alloy NbTiAl.eam.alloy NULL Ti Nb NULLerror:Pair coeff for hybrid has invalid style

Hope someone give me some advice. Thank you in advance.
Best regards,

you have a syntax error, because you are not following the pair_coeff syntax for hybrid styles correctly.
however, even if you had an input with correct syntax, your simulation would be garbage, because you cannot use manybody potentials in a pairwise additive fashion. to have meaningful results, you best need to find a parameterization, that encompasses all three elements. there are databases for that and you can search the published literature. there is also a function that would allow automated mixing of (pairwise) terms when using pair style eam (not eam/fs or eam/alloy) with 3 different single element files for each element.

pair style hybrid does only do what is called “mechanical coupling” of potentials, and thus for eam family pair styles the embedding energy contributions would be missing and you MUST be using the pair_coeff * * syntax, which makes using only the mixed terms impossible.

this has been explained many, many times on this mailing list. please search through the mailing list archive, if you want to know more details about why what you are trying to do is a very, VERY bad idea.