def test_phasediagram():
"""Test example from docs."""
refs = [('Cu', 0.0), ('Au', 0.0), ('CuAu2', -0.2), ('CuAu', -0.5),
('Cu2Au', -0.7)]
pd = PhaseDiagram(refs)
energy, indices, coefs = pd.decompose('Cu3Au')
assert energy == pytest.approx(-0.7)
assert (indices == [4, 0]).all()
assert coefs == pytest.approx(1.0)
# creates: cuau.png
import matplotlib.pyplot as plt
from ase.phasediagram import PhaseDiagram
refs = [('Cu', 0.0),
('Au', 0.0),
('CuAu2', -0.2),
('CuAu', -0.5),
('Cu2Au', -0.7)]
pd = PhaseDiagram(refs)
pd.plot(show=False)
plt.savefig('cuau.png')
print(pd.decompose('Cu3Au'))
from __future__ import print_function
import ase.db
from ase.phasediagram import PhaseDiagram
con = ase.db.connect('cubic_perovskites.db')
references = [(row.formula, row.energy)
for row in con.select('reference')]
fd = open('abo3.csv', 'w')
print('# id, formula, heat of formation [eV/atom]', file=fd)
for row in con.select(combination='ABO3'):
pd = PhaseDiagram(references, filter=row.formula, verbose=False)
energy = pd.decompose(row.formula)[0]
heat = (row.energy - energy) / row.natoms
if (heat < 0.21 and
(3.1 > row.gllbsc_ind_gap > 1.4 or
3.1 > row.gllbsc_dir_gap > 1.4) and
(row.VB_ind - 4.5 > 1.23 and row.CB_ind - 4.5 < 0 or
row.VB_dir - 4.5 > 1.23 and row.CB_dir - 4.5 < 0)):
formula = row.A_ion + row.B_ion + row.anion
print('{0}, {1}, {2:.3f}'.format(row.id, formula, heat), file=fd)
# creates: cuau.png
import matplotlib.pyplot as plt
from ase.phasediagram import PhaseDiagram
refs = [('Cu', 0.0),
('Au', 0.0),
('CuAu2', -0.2),
('CuAu', -0.5),
('Cu2Au', -0.7)]
pd = PhaseDiagram(refs)
pd.plot()
plt.savefig('cuau.png')
print(pd.decompose('Cu3Au'))
