# Define unit set and class of atomic model
units metal
atom_style atomic

# Periodic boundary conditions along all three dimensions
boundary p p p

# Create an FCC lattice with the lattice spacing supplied supplied by the user
# using a single conventional (orthogonal) unit cell
lattice fcc sed_initial_lattice_constant_string
region box block 0 1 0 1 0 1 units lattice
create_box 1 box
create_atoms 1 box
mass 1 39.948

# Specify which KIM Model to use, letting LAMMPS compute the virial/pressure
pair_style kim LAMMPSvirial sed_model_string
pair_coeff * * Ar

# Set what thermodynamic information to print to log
thermo_style custom step atoms xlo xhi ylo yhi zlo zhi pe press pxx pyy pzz pxy pxz pyz
thermo 10 # Print every 10 timesteps

# Set what information to write to dump file
dump id all custom 10 output/lammps.dump id type x y z fx fy fz
dump_modify id format "%d %d %16.7f %16.7f %16.7f %16.7f %16.7f %16.7f"

# Set boundary conditions to be stress-free
fix 1 all box/relax iso 0.0

# Perform static minimization using the Polack-Ribiere conjugate gradient method.
# The first argument is a convergence tolerance for the energy, the second argument
# is a convergence tolerance for the forces, and the latter two arguments set the
# maximum number of allowed iterations and force/energy evaluations, respectively.
minimize 1e-16 1e-16 2000 100000

# Define auxiliary variables to contain cohesive energy and equilibrium lattice constant
variable poteng    equal "c_thermo_pe"
variable natoms    equal "count(all)"
variable ecohesive equal "-v_poteng/v_natoms"
variable pressure  equal "c_thermo_press"
variable a         equal "lx"

# Output cohesive energy and equilibrium lattice constant
print "Final pressure = ${pressure} bar"
print "Cohesive energy = ${ecohesive} eV/atom"
print "Equilibrium lattice constant = ${a} angstrom"