from ATK.KohnSham import *

# Specify atoms, positions and Bravais lattice
atom = [Iron]
position = [(0.0,0.0,0.0)]*Angstrom
unitcell = BodyCenteredCubic(2.87*Angstrom)

# Combine atom, positions and lattice into a
# crystal structure
Iron = BulkConfiguration(
    bravais_lattice=unitcell,
    elements=atom,
    cartesian_coordinates=position
    )

# Specify calculation dependent parameters
kpoints = brillouinZoneIntegrationParameters((10,10,10))

initial_density = electronDensityParameters(
    mesh_cutoff=100*Rydberg,
    initial_scaled_spin=[0.5]
    )

dft_iron = KohnShamMethod(
    electron_density_parameters = initial_density,
    brillouin_zone_integration_parameters=kpoints,
    )
# Start calculation and store results in a variable
scf_iron = dft_iron.apply(Iron)