SiC simulation

Hello everyone,

I am a new user of Lammps, trying to simulate 3C-SiC strucuture. I have created the structure by following commands

---------- Initialize Simulation ---------------------

units metal
dimension 3
boundary p p p
atom_style atomic

---------- Create Atoms ---------------------

lattice custom 4.35 origin 0.0 0.0 0.0 orient x 1 0 0 orient y 0 1 0 orient z 0 0 1 &
basis 0.0 0.0 0.0 &
basis 0.5 0.0 0.5 &
basis 0.0 0.5 0.5 &
basis 0.5 0.5 0.0 &
basis 0.25 0.25 0.25 &
basis 0.75 0.25 0.75 &
basis 0.25 0.75 0.75 &
basis 0.75 0.75 0.25 &
a1 1.0 0.0 0.0 &
a2 0.0 1.0 0.0 &
a3 0.0 0.0 1.0
region box block -20 20 -20 20 -20 20
create_box 2 box
create_atoms 1 box &
basis 1 1 &
basis 2 1 &
basis 3 1 &
basis 4 1 &
basis 5 2 &
basis 6 2 &
basis 7 2 &
basis 8 2
mass 1 28.08
mass 2 12.01

---------- Define Interatomic Potential ---------------------

pair_style tersoff
pair_coeff * * SiC.tersoff Si Si Si Si C C C C

After executing I got the error message like " Incorrect Arguments for pair coefficient ". Can anyone please suggest to solve this issue. Thanks.

Md. Riaz Kayser
PhD Candidate

Multiscale Mechanics and Physics Lab

University of Texas at Arlington.

Hello everyone,
I am a new user of Lammps, trying to simulate 3C-SiC strucuture. I have
created the structure by following commands

# ---------- Initialize Simulation ---------------------
units metal
dimension 3
boundary p p p
atom_style atomic

# ---------- Create Atoms ---------------------

lattice custom 4.35 origin 0.0 0.0 0.0 orient x 1 0 0 orient y 0 1 0 orient
z 0 0 1 &
basis 0.0 0.0 0.0 &
basis 0.5 0.0 0.5 &
basis 0.0 0.5 0.5 &
basis 0.5 0.5 0.0 &
basis 0.25 0.25 0.25 &
basis 0.75 0.25 0.75 &
basis 0.25 0.75 0.75 &
basis 0.75 0.75 0.25 &
a1 1.0 0.0 0.0 &
a2 0.0 1.0 0.0 &
a3 0.0 0.0 1.0
region box block -20 20 -20 20 -20 20
create_box 2 box
create_atoms 1 box &
basis 1 1 &
basis 2 1 &
basis 3 1 &
basis 4 1 &
basis 5 2 &
basis 6 2 &
basis 7 2 &
basis 8 2
mass 1 28.08
mass 2 12.01

# ---------- Define Interatomic Potential ---------------------
pair_style tersoff
pair_coeff * * SiC.tersoff Si Si Si Si C C C C

After executing I got the error message like " Incorrect Arguments for pair
coefficient ". Can anyone please suggest to solve this issue. Thanks.

you define a box with support for two atom types but refer to 8 types
in your pair_coeff statement. that is wrong and LAMMPS tells you that.

please re-read the documentation,

axel

Thanks. I went through the manual 1448 page and from there I thought I have to put all the atoms in a unit cell. But now I think I have to put only no of different atoms in the whole simulation. Thanks once again.
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