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Hello,

I want to simulate Ni-Ti-C systems. I have one MEAM potential for Ni-C and one MEAM potential for FeTiC. Also, I have EAM potential for NiTi. I was wondering if that’s possible for lammps to use these three potentials to define the interaction between Ni-Ti-C atoms.

If yes, Could please help me about the pair style and pair coeff commands.

Thank you very much,

Hello Yazdandoost,

To my knowledge, we can use three potentials to define the interaction between atoms through “pair_style hybrid”. You might need to look into hybrid pair_style to set up pair style and pair coeff.

Regards
Raghuram

Hello Yazdandoost,

To my knowledge, we can use three potentials to define the interaction between atoms through “pair_style hybrid”. You might need to look into hybrid pair_style to set up pair style and pair coeff.

technically, this may be possible, but particularly for EAM or MEAM, this is a very, VERY bad idea. these potentials are not pairwise additive and you cannot simply mix and match them, and most importantly, in “hybrid” mode, you don’t account for contributions of the different atoms to the embedding energy of the other hybrid substyles.

the proper way to do this, is to find a set of parameters, that covers the entire triple of elements. please note, that in MEAM the potential parameters are a bit more complex. and that you have a basic generic contribution and then specific “overrides” for specific pairs and triples of elements. those files have to be used extremely carefully after thorough studying of the documentation.
since the individual contributions in the second file are indexed numerically by the order in while the first set of atoms are “extracted” from the general library. thus merging such files is particularly difficult and requires sufficient experience.

axel.

Thank you very much for your answer. I apreciate it.

Thank you very much for you answer. Appreciate it.