LAMMPS version: 29Aug2024
Hi,
I have a bit of a hard time interpreting the documentation for pair_style eam/alloy (pair_style eam command — LAMMPS documentation). When discussing the example pair_coeff * * NiAlH_jea.eam.alloy Ni Ni Ni Al it states:
The first 2 arguments must be * * so as to span all LAMMPS atom types. The first three Ni arguments map LAMMPS atom types 1,2,3 to the Ni element in the setfl file. The final Al argument maps LAMMPS atom type 4 to the Al element in the setfl file. Note that there is no requirement that your simulation use all the elements specified by the setfl file.
However, later on it states:
In a DYNAMO setfl file, line 4 only lists Nelements = the # of elements in the setfl file. For LAMMPS, the element name (Ni, Cu, etc) of each element must be added to the line, in the order the elements appear in the file.
The ‘order’ is here referred to the order in the .eam.alloy potential file or in the input LAMMPS file (i.e. when specifying the pair_coeff command)?
I am working with a EAM potential for CuAgAuNiPdPtAlPbFeMoTaWMgCoTiZr (in this order, Interatomic Potentials Repository), and I am simulating the spreding of a molten Al droplet on a WMo crystal slab. In my input .data files, type 1 corresponds to Al, while 2 and 3 respectively to W and Mo. According to the first statement, I should define the pair potential as:
pair_coeff * * ../../potential-files/eam/CuAgAuNiPdPtAlPbFeMoTaWMgCoTiZr_Zhou04.eam.alloy Al W Mo
But according to the second statement there may be way to specify the pair_coeff command, as there’s no order that can satisfy both the potential file and the data files.