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: ktao-2d.png, ktao-3d.png
import matplotlib.pyplot as plt
from ase.phasediagram import PhaseDiagram
references = [('K', 0), ('Ta', 0), ('O2', 0), ('K3TaO8', -16.167),
('KO2', -2.288), ('KO3', -2.239), ('Ta2O5', -19.801),
('TaO3', -8.556), ('TaO', -1.967), ('K2O', -3.076),
('K2O2', -4.257), ('KTaO3', -13.439)]
pd = PhaseDiagram(references)
for d in [2, 3]:
pd.plot(dims=d, show=False)
plt.savefig('ktao-{}d.png'.format(d))
import numpy as np
import matplotlib.pyplot as plt
from ase.phasediagram import PhaseDiagram
from ase.db import connect
from ase.io import write
db = connect('hull.db')
# Select the evaluated candidates and retrieve the chemical formula and mixing
# energy for the phase diagram
refs = []
dcts = list(db.select('relaxed=1'))
for dct in dcts:
refs.append((dct.formula, -dct.raw_score))
pd = PhaseDiagram(refs)
ax = pd.plot(
show=not True, # set to True to show plot
only_label_simplices=True)
plt.savefig('hull.png')
# View the simplices of the convex hull
simplices = []
toview = sorted(np.array(dcts)[pd.hull], key=lambda x: x.mass)
for dct in toview:
simplices.append(dct.toatoms())
write('hull.traj', simplices)
import numpy as np
from ase.phasediagram import PhaseDiagram
from ase.db import connect
from ase.io import write
db = connect('hull.db')
# Select the evaluated candidates and retrieve the chemical formula and mixing
# energy for the phase diagram
refs = []
dcts = list(db.select('relaxed=1'))
for dct in dcts:
refs.append((dct.formula, -dct.raw_score))
pd = PhaseDiagram(refs)
pd.plot(only_label_simplices=True)
# View the simplices of the convex hull
simplices = []
toview = sorted(np.array(dcts)[pd.hull], key=lambda x: x.mass)
for dct in toview:
simplices.append(dct.toatoms())
write('hull.traj', simplices)
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(show=False)
plt.savefig('cuau.png')
print(pd.decompose('Cu3Au'))
# 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'))
# creates: ktao-2d.png, ktao-3d.png
import matplotlib.pyplot as plt
from ase.phasediagram import PhaseDiagram
references = [('K', 0), ('Ta', 0), ('O2', 0),
('K3TaO8', -16.167), ('KO2', -2.288),
('KO3', -2.239), ('Ta2O5', -19.801),
('TaO3', -8.556), ('TaO', -1.967),
('K2O', -3.076), ('K2O2', -4.257),
('KTaO3', -13.439)]
pd = PhaseDiagram(references)
for d in [2, 3]:
pd.plot(dims=d, show=False)
plt.savefig('ktao-{}d.png'.format(d))