Incorrect args for pair style meam coefficients (src/MEAM/pair_meam.cpp:204)

LAMMPS LAMMPS General Discussion
1

I want to build a simple NiTi molecular dynamics model composed of 50%Ni and 50%Ti atoms, and choose the atomic potential (2NN-MEAM) based on the second nearest neighbor modified embedded atom theory as the potential function, but my lammps calculation process keeps reporting errors, I would like to ask why?
Here is my code:

units metal
dimension 3
boundary p p p
atom_style atomic

region box block 0 144.77 0 145.02 0 145.02

lattice bcc 3.0
create_box 2 box
create_atoms 1 box
create_atoms 2 box

mass 1 58.69 #NI
mass 2 47.87 #TI

pair_style meam
pair_coeff * * library.meam Ni Ti NiTi.meam Ni Ti
write_data NiTi_model.xyz

velocity all create 300.0 123456
fix 1 all nve

timestep 0.001
thermo 100
run 10000

2

Hi @augus,

You’re more likely to get relevant help by providing the LAMMPS version you are using and following the forum guidelines.

At the moment it is hard to tell what goes wrong without more info. Are you sure you copied the requested files in the directory where you execute your script and that no invisible characters are in your pair_coeff line?

This asides, I don’t think the following set of commands does what you think it does:

region box block 0 144.77 0 145.02 0 145.02

lattice bcc 3.0
create_box 2 box
create_atoms 1 box
create_atoms 2 box

You’re likely to get other errors once you solve the pair_coeff issue.

3

I am using lammps(mpi)

4

This is not helping. See 1.2. What does a LAMMPS version mean — LAMMPS documentation

This line as copied to the forum is syntactically correct and does not produce the error you reported.

The input is still problematic because you are creating always pairs of two atoms directly on top of each other as Germain already pointed out. This will lead to invalid forces.