def get_dos(
model,
posinp,
device="cpu",
supercell=(6, 6, 6),
qpoints=[30, 30, 30],
npts=1000,
width=0.004,
):
if isinstance(posinp, str):
atoms = posinp_to_ase_atoms(Posinp.from_file(posinp))
elif isinstance(posinp, Posinp):
atoms = posinp_to_ase_atoms(posinp)
else:
raise ValueError("The posinp variable is not recognized.")
if isinstance(model, str):
model = load_model(model, map_location=device)
elif isinstance(model, torch.nn.Module):
pass
else:
raise ValueError("The model variable is not recognized.")
# Bugfix to make older models work with PyTorch 1.6
# Hopefully temporary
for mod in model.modules():
if not hasattr(mod, "_non_persistent_buffers_set"):
mod._non_persistent_buffers_set = set()
assert len(supercell) == 3, "Supercell should be a length 3 object."
assert len(qpoints) == 3, "Qpoints should be a length 3 object."
supercell = tuple(supercell)
cutoff = float(model.state_dict()
["representation.interactions.0.cutoff_network.cutoff"])
calculator = SpkCalculator(
model,
device=device,
energy="energy",
forces="forces",
environment_provider=AseEnvironmentProvider(cutoff),
)
ph = Phonons(atoms, calculator, supercell=supercell, delta=0.02)
ph.run()
ph.read(acoustic=True)
dos = ph.get_dos(kpts=qpoints).sample_grid(npts=npts, width=width)
ph.clean()
return Dos(dos.energy * 8065.6, dos.weights[0])
def calculate_phonons(x):
# Setup crystal and EMT calculator
atoms = bulk('Al', 'fcc', a=x) #4.05)
# Phonon calculator
N = 7
ph = Phonons(atoms, EMT(), supercell=(N, N, N), delta=0.05)
ph.run()
# Read forces and assemble the dynamical matrix
ph.read(acoustic=True)
ph.clean()
path = atoms.cell.bandpath('GXULGK', npoints=100)
bs = ph.get_band_structure(path)
dos = ph.get_dos(kpts=(20, 20, 20)).sample_grid(npts=100, width=1e-3)
forces = ph.get_force_constant()
print(forces)
# Plot the band structure and DOS:
import matplotlib.pyplot as plt
fig = plt.figure(1, figsize=(8, 4), dpi=300)
ax = fig.add_axes([.12, .07, .67, .85])
emax = 0.035
bs.plot(ax=ax, emin=-0.01, emax=emax)
dosax = fig.add_axes([.8, .07, .17, .85])
dosax.fill_between(dos.weights[0],
dos.energy,
y2=0,
color='grey',
edgecolor='k',
lw=1)
dosax.set_ylim(-0.01, emax)
dosax.set_yticks([])
dosax.set_xticks([])
dosax.set_xlabel("DOS", fontsize=18)
fig.savefig('Al_phonon.png')
return
# Setup crystal and EMT calculator
atoms = bulk('Al', 'fcc', a=4.05)
# Phonon calculator
N = 7
ph = Phonons(atoms, EMT(), supercell=(N, N, N), delta=0.05)
ph.run()
# Read forces and assemble the dynamical matrix
ph.read(acoustic=True)
ph.clean()
path = atoms.cell.bandpath('GXULGK', npoints=100)
bs = ph.get_band_structure(path)
dos = ph.get_dos(kpts=(20, 20, 20)).sample_grid(npts=100, width=1e-3)
# Plot the band structure and DOS:
import matplotlib.pyplot as plt
fig = plt.figure(1, figsize=(7, 4))
ax = fig.add_axes([.12, .07, .67, .85])
emax = 0.035
bs.plot(ax=ax, emin=0.0, emax=emax)
dosax = fig.add_axes([.8, .07, .17, .85])
dosax.fill_between(dos.weights[0],
dos.energy,
y2=0,
color='grey',
edgecolor='k',
