elements = [ Carbon ] * 2
coordinates = [
    ( 0.00, 0.00, 0.00 ),
    ( 0.25, 0.25, 0.25 )
    ]
diamond_lattice = FaceCenteredCubic( 3.567 * Ang )
diamond = BulkConfiguration(
    diamond_lattice,
    elements,
    fractional_coordinates = coordinates
    )