def test_bulk():
    from ase import Atoms
    from ase.calculators.crystal import CRYSTAL

    with open('basis', 'w') as fd:
        fd.write("""6 4
    0 0 6 2.0 1.0
     3048.0 0.001826
     456.4 0.01406
     103.7 0.06876
     29.23 0.2304
     9.349 0.4685
     3.189 0.3628
    0 1 2 4.0 1.0
     3.665 -0.3959 0.2365
     0.7705 1.216 0.8606
    0 1 1 0.0 1.0
     0.26 1.0 1.0 
    0 3 1 0.0 1.0
     0.8 1.0
    """)

    a0 = 5.43
    bulk = Atoms('Si2', [(0, 0, 0),
                         (0.25, 0.25, 0.25)],
                 pbc=True)
    b = a0 / 2
    bulk.set_cell([(0, b, b),
                   (b, 0, b),
                   (b, b, 0)], scale_atoms=True)

    bulk.calc = CRYSTAL(
        label='Si2',
        guess=True,
        basis='sto-3g',
        xc='PBE',
        kpts=(2, 2, 2),
        otherkeys=['scfdir', 'anderson',
                   ['maxcycles', '500'],
                   ['toldee', '6'],
                   ['tolinteg', '7 7 7 7 14'],
                   ['fmixing', '50']])

    final_energy = bulk.get_potential_energy()
    assert abs(final_energy + 15564.787949) < 1.0