def test_Ag_Cu100():
from math import sqrt
from ase import Atom, Atoms
from ase.neb import NEB
from ase.constraints import FixAtoms
from ase.vibrations import Vibrations
from ase.calculators.emt import EMT
from ase.optimize import QuasiNewton, BFGS
# Distance between Cu atoms on a (100) surface:
d = 3.6 / sqrt(2)
initial = Atoms('Cu',
positions=[(0, 0, 0)],
cell=(d, d, 1.0),
pbc=(True, True, False))
initial *= (2, 2, 1) # 2x2 (100) surface-cell
# Approximate height of Ag atom on Cu(100) surfece:
h0 = 2.0
initial += Atom('Ag', (d / 2, d / 2, h0))
# Make band:
images = [initial.copy() for i in range(6)]
neb = NEB(images, climb=True)
# Set constraints and calculator:
constraint = FixAtoms(range(len(initial) - 1))
for image in images:
image.calc = EMT()
image.set_constraint(constraint)
# Displace last image:
images[-1].positions[-1] += (d, 0, 0)
# Relax height of Ag atom for initial and final states:
dyn1 = QuasiNewton(images[0])
dyn1.run(fmax=0.01)
dyn2 = QuasiNewton(images[-1])
dyn2.run(fmax=0.01)
# Interpolate positions between initial and final states:
neb.interpolate()
for image in images:
print(image.positions[-1], image.get_potential_energy())
dyn = BFGS(neb, trajectory='mep.traj')
dyn.run(fmax=0.05)
for image in images:
print(image.positions[-1], image.get_potential_energy())
a = images[0]
vib = Vibrations(a, [4])
vib.run()
print(vib.get_frequencies())
vib.summary()
print(vib.get_mode(-1))
vib.write_mode(-1, nimages=20)
def test_consistency_with_vibrationsdata(self, testdir, n2_emt):
atoms = n2_emt
vib = Vibrations(atoms)
vib.run()
vib_data = vib.get_vibrations()
assert_array_almost_equal(vib.get_energies(), vib_data.get_energies())
# Compare the last mode as the others may be re-ordered by negligible
# energy changes
assert_array_almost_equal(vib.get_mode(5), vib_data.get_modes()[5])
def test_vib():
import os
from ase import Atoms
from ase.calculators.emt import EMT
from ase.optimize import QuasiNewton
from ase.vibrations import Vibrations
from ase.thermochemistry import IdealGasThermo
n2 = Atoms('N2', positions=[(0, 0, 0), (0, 0, 1.1)], calculator=EMT())
QuasiNewton(n2).run(fmax=0.01)
vib = Vibrations(n2)
vib.run()
freqs = vib.get_frequencies()
print(freqs)
vib.summary()
print(vib.get_mode(-1))
vib.write_mode(n=None, nimages=20)
vib_energies = vib.get_energies()
for image in vib.iterimages():
assert len(image) == 2
thermo = IdealGasThermo(vib_energies=vib_energies,
geometry='linear',
atoms=n2,
symmetrynumber=2,
spin=0)
thermo.get_gibbs_energy(temperature=298.15, pressure=2 * 101325.)
assert vib.clean(empty_files=True) == 0
assert vib.clean() == 13
assert len(list(vib.iterimages())) == 13
d = dict(vib.iterdisplace(inplace=False))
for name, atoms in vib.iterdisplace(inplace=True):
assert d[name] == atoms
vib = Vibrations(n2)
vib.run()
assert vib.combine() == 13
assert (freqs == vib.get_frequencies()).all()
vib = Vibrations(n2)
assert vib.split() == 1
assert (freqs == vib.get_frequencies()).all()
assert vib.combine() == 13
# Read the data from other working directory
dirname = os.path.basename(os.getcwd())
os.chdir('..') # Change working directory
vib = Vibrations(n2, name=os.path.join(dirname, 'vib'))
assert (freqs == vib.get_frequencies()).all()
assert vib.clean() == 1
def test_vibration_on_surface(self, testdir):
from ase.build import fcc111, add_adsorbate
ag_slab = fcc111('Ag', (4, 4, 2), a=2)
n2 = Atoms('N2',
positions=[[0., 0., 0.], [0., np.sqrt(2),
np.sqrt(2)]])
add_adsorbate(ag_slab, n2, height=1, position='fcc')
# Add an interaction between the N atoms
hessian_bottom_corner = np.zeros((2, 3, 2, 3))
hessian_bottom_corner[-1, :, -2] = [1, 1, 1]
hessian_bottom_corner[-2, :, -1] = [1, 1, 1]
hessian = np.zeros((34, 3, 34, 3))
hessian[32:, :, 32:, :] = hessian_bottom_corner
ag_slab.calc = ForceConstantCalculator(hessian.reshape(
(34 * 3, 34 * 3)),
ref=ag_slab.copy(),
f0=np.zeros((34, 3)))
# Check that Vibrations with restricted indices returns correct Hessian
vibs = Vibrations(ag_slab, indices=[-2, -1])
vibs.run()
vibs.read()
assert_array_almost_equal(vibs.get_vibrations().get_hessian(),
hessian_bottom_corner)
# These should blow up if the vectors don't match number of atoms
vibs.summary()
vibs.write_jmol()
for i in range(6):
# Frozen atoms should have zero displacement
assert_array_almost_equal(vibs.get_mode(i)[0], [0., 0., 0.])
# The N atoms should have finite displacement
assert np.all(vibs.get_mode(i)[-2:, :])
def get_modes(self,atm,freqname="vib."):
for f in [f for f in os.listdir(".") if freqname in f and '.pckl' in f]:
os.remove(f)
new_target = open(os.devnull, "w")
old_target, sys.stdout = sys.stdout, new_target
atm.set_calculator(ANIENS(self.ens))
vib = Vibrations(atm, nfree=2, name=freqname)
vib.run()
freq = vib.get_frequencies()
modes = np.stack(vib.get_mode(i) for i in range(freq.size))
vib.clean()
sys.stdout = old_target
return modes
def test_vibrations_methods(self, testdir, random_dimer):
vib = Vibrations(random_dimer)
vib.run()
vib_energies = vib.get_energies()
for image in vib.iterimages():
assert len(image) == 2
thermo = IdealGasThermo(vib_energies=vib_energies,
geometry='linear',
atoms=vib.atoms,
symmetrynumber=2,
spin=0)
thermo.get_gibbs_energy(temperature=298.15,
pressure=2 * 101325.,
verbose=False)
with open(self.logfile, 'w') as fd:
vib.summary(log=fd)
with open(self.logfile, 'rt') as fd:
log_txt = fd.read()
assert log_txt == '\n'.join(
VibrationsData._tabulate_from_energies(vib_energies)) + '\n'
last_mode = vib.get_mode(-1)
scale = 0.5
assert_array_almost_equal(
vib.show_as_force(-1, scale=scale, show=False).get_forces(),
last_mode * 3 * len(vib.atoms) * scale)
vib.write_mode(n=3, nimages=5)
for i in range(3):
assert not Path('vib.{}.traj'.format(i)).is_file()
mode_traj = ase.io.read('vib.3.traj', index=':')
assert len(mode_traj) == 5
assert_array_almost_equal(mode_traj[0].get_all_distances(),
random_dimer.get_all_distances())
with pytest.raises(AssertionError):
assert_array_almost_equal(mode_traj[4].get_all_distances(),
random_dimer.get_all_distances())
assert vib.clean(empty_files=True) == 0
assert vib.clean() == 13
assert len(list(vib.iterimages())) == 13
d = dict(vib.iterdisplace(inplace=False))
for name, image in vib.iterdisplace(inplace=True):
assert d[name] == random_dimer
def test_consistency_with_vibrationsdata(self, testdir, random_dimer):
vib = Vibrations(random_dimer, delta=1e-6, nfree=4)
vib.run()
vib_data = vib.get_vibrations()
assert_array_almost_equal(vib.get_energies(), vib_data.get_energies())
for mode_index in range(3 * len(vib.atoms)):
assert_array_almost_equal(vib.get_mode(mode_index),
vib_data.get_modes()[mode_index])
# Hessian should be close to the ForceConstantCalculator input
assert_array_almost_equal(random_dimer.calc.D,
vib_data.get_hessian_2d(),
decimal=6)
def test_vibrations_on_surface(self, testdir):
atoms = self.n2_on_ag.copy()
atoms.calc = EMT()
vibs = Vibrations(atoms, indices=[-2, -1])
vibs.run()
freqs = vibs.get_frequencies()
assert len(freqs) == 6
vib_data = vibs.get_vibrations()
assert_array_almost_equal(freqs, vib_data.get_frequencies())
# These should blow up if the vectors don't match number of atoms
vibs.summary()
vibs.write_jmol()
for i in range(6):
# Frozen atoms should have zero displacement
assert_array_almost_equal(vibs.get_mode(i)[0], [0., 0., 0.])
# At least one of the N atoms should have finite displacement
# (It's a strange test system, the N aren't interacting.)
assert np.any(vibs.get_mode(i)[-2:, :])
from __future__ import print_function
from ase import Atoms
from ase.calculators.emt import EMT
from ase.optimize import QuasiNewton
from ase.vibrations import Vibrations
from ase.thermochemistry import IdealGasThermo
n2 = Atoms('N2',
positions=[(0, 0, 0), (0, 0, 1.1)],
calculator=EMT())
QuasiNewton(n2).run(fmax=0.01)
vib = Vibrations(n2)
vib.run()
print(vib.get_frequencies())
vib.summary()
print(vib.get_mode(-1))
vib.write_mode(n=None, nimages=20)
vib_energies = vib.get_energies()
for image in vib.iterimages():
assert len(image) == 2
thermo = IdealGasThermo(vib_energies=vib_energies, geometry='linear',
atoms=n2, symmetrynumber=2, spin=0)
thermo.get_gibbs_energy(temperature=298.15, pressure=2 * 101325.)
assert vib.clean(empty_files=True) == 0
assert vib.clean() == 13
assert len(list(vib.iterimages())) == 13
d = dict(vib.iterdisplace(inplace=False))
from ase import *
from ase.vibrations import Vibrations
n2 = Atoms('N2',
positions=[(0, 0, 0), (0, 0, 1.1)],
calculator=EMT())
QuasiNewton(n2).run(fmax=0.01)
vib = Vibrations(n2)
vib.run()
print vib.get_frequencies()
vib.summary()
print vib.get_mode(-1)
vib.write_mode(-1, nimages=20)
from ase import Atoms
from ase.calculators.emt import EMT
from ase.optimize import QuasiNewton
from ase.vibrations import Vibrations
from ase.thermochemistry import IdealGasThermo
n2 = Atoms('N2',
positions=[(0, 0, 0), (0, 0, 1.1)],
calculator=EMT())
QuasiNewton(n2).run(fmax=0.01)
vib = Vibrations(n2)
vib.run()
print vib.get_frequencies()
vib.summary()
print vib.get_mode(-1)
vib.write_mode(-1, nimages=20)
vib_energies = vib.get_energies()
thermo = IdealGasThermo(vib_energies=vib_energies, geometry='linear',
atoms=n2, symmetrynumber=2, spin=0)
thermo.get_free_energy(temperature=298.15, pressure=2*101325.)
from ase import Atoms
from ase.calculators.emt import EMT
from ase.optimize import QuasiNewton
from ase.vibrations import Vibrations
from ase.thermochemistry import IdealGasThermo
n2 = Atoms('N2',
positions=[(0, 0, 0), (0, 0, 1.1)],
calculator=EMT())
QuasiNewton(n2).run(fmax=0.01)
vib = Vibrations(n2)
vib.run()
print(vib.get_frequencies())
vib.summary()
print(vib.get_mode(-1))
vib.write_mode(n=None, nimages=20)
vib_energies = vib.get_energies()
thermo = IdealGasThermo(vib_energies=vib_energies, geometry='linear',
atoms=n2, symmetrynumber=2, spin=0)
thermo.get_gibbs_energy(temperature=298.15, pressure=2 * 101325.)
def test_vibrations(self, testdir, n2_emt, n2_optimized):
atoms = n2_emt
vib = Vibrations(atoms)
vib.run()
freqs = vib.get_frequencies()
vib.write_mode(n=None, nimages=5)
vib.write_jmol()
vib_energies = vib.get_energies()
for image in vib.iterimages():
assert len(image) == 2
thermo = IdealGasThermo(vib_energies=vib_energies,
geometry='linear',
atoms=atoms,
symmetrynumber=2,
spin=0)
thermo.get_gibbs_energy(temperature=298.15,
pressure=2 * 101325.,
verbose=False)
vib.summary(log=self.logfile)
with open(self.logfile, 'rt') as f:
log_txt = f.read()
assert log_txt == vibrations_n2_log
mode1 = vib.get_mode(-1)
assert_array_almost_equal(mode1,
[[0., 0., -0.188935], [0., 0., 0.188935]])
assert_array_almost_equal(
vib.show_as_force(-1, show=False).get_forces(),
[[0., 0., -2.26722e-1], [0., 0., 2.26722e-1]])
for i in range(3):
assert not os.path.isfile('vib.{}.traj'.format(i))
mode_traj = ase.io.read('vib.3.traj', index=':')
assert len(mode_traj) == 5
assert_array_almost_equal(mode_traj[0].get_all_distances(),
atoms.get_all_distances())
with pytest.raises(AssertionError):
assert_array_almost_equal(mode_traj[4].get_all_distances(),
atoms.get_all_distances())
with open('vib.xyz', 'rt') as f:
jmol_txt = f.read()
assert jmol_txt == jmol_txt_ref
assert vib.clean(empty_files=True) == 0
assert vib.clean() == 13
assert len(list(vib.iterimages())) == 13
d = dict(vib.iterdisplace(inplace=False))
for name, image in vib.iterdisplace(inplace=True):
assert d[name] == atoms
atoms2 = n2_emt
vib2 = Vibrations(atoms2)
vib2.run()
assert_array_almost_equal(freqs, vib.get_frequencies())
# write/read the data from another working directory
atoms3 = n2_optimized.copy() # No calculator needed!
workdir = os.path.abspath(os.path.curdir)
try:
os.mkdir('run_from_here')
os.chdir('run_from_here')
vib = Vibrations(atoms3, name=os.path.join(os.pardir, 'vib'))
assert_array_almost_equal(freqs, vib.get_frequencies())
assert vib.clean() == 13
finally:
os.chdir(workdir)
if os.path.isdir('run_from_here'):
os.rmdir('run_from_here')
# Get the forces again
print('Forces:')
print(geometry.get_forces())
# Run the vibrational analysis
vib = Vibrations(geometry, nfree=2)
vib.run()
print(vib.summary())
print(vib.get_zero_point_energy())
# Get freqs
f = vib.get_frequencies()
# Print modes + freq
for i in range(0, len(f)):
print('Mode(' + str(i) + ') Freq: ' + "{:.7e}".format(f[i]))
print(vib.get_mode(i))
'''
# We will alse need to use these functions to get thermo-chem data
thermo = IdealGasThermo(vib_energies=vib_energies,
potentialenergy=potentialenergy,
atoms=atoms,
geometry='linear',
symmetrynumber=2, spin=0)
G = thermo.get_gibbs_energy(temperature=298.15, pressure=101325.)
'''
# remove mode pckl files
vib.clean()