mixing of pair style eam/alloy potentials

Dear all,

I have two eam.alloy type potential files for two elements (i.e., for type 1 potential file is X.eam.alloy, for type 2 Y.eam.alloy)

How to mix them such that i can get XY cross interaction

I tried the following commands

pair_style hybrid eam/alloy
pair_coeff * * eam/alloy X.eam.alloy X NULL
pair_coeff 2 2 eam/alloy Y.eam.alloy Y
pair_modify mix geometric

But i am getting the error as

‘incorrect args for pair co-efficients’

please help me


You can't mix eam/alloy potentials that way.
You can use single-element eam files that
way, e.g. assign one to each element via
different types, and LAMMPS will mix
them for you. But an eam.alloy file has
the mixing inside it. Thus you need to
create one eam.alloy file that covers all
the elements in your system and assign
it once as pair_coeff * * file ...

The pait_style eam doc page explains all of this.