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"""
Function-like objects that creates cubic clusters.
"""
import numpy as np
from ase.cluster.factory import ClusterFactory
from ase.data import reference_states as _refstate
class HexagonalFactory(ClusterFactory):
spacegroup = 191
xtal_name = 'hexagonal'
def get_lattice_constant(self):
"Get the lattice constant of an element with cubic crystal structure."
symmetry = _refstate[self.atomic_numbers[0]]['symmetry']
if symmetry != self.xtal_name:
raise ValueError(f"Cannot guess the {self.xtal_name} " +
"lattice constant of an element with crystal " +
f"structure {symmetry}.")
return _refstate[self.atomic_numbers[0]].copy()
def set_basis(self):
lattice = self.lattice_constant
if isinstance(lattice, dict):
a = lattice['a']
try:
c = lattice['c']
except KeyError:
c = a * lattice['c/a']
else:
if len(lattice) == 2:
(a, c) = lattice
else:
raise ValueError(
f"Improper lattice constants for {self.xtal_name} crystal.")
self.lattice_constant = (a, c)
self.lattice_basis = np.array([[a, 0., 0.],
[-a / 2., a * np.sqrt(3.) / 2., 0.],
[0., 0., c]])
self.resiproc_basis = self.get_resiproc_basis(self.lattice_basis)
def set_surfaces_layers(self, surfaces, layers):
for i, s in enumerate(surfaces):
if len(s) == 4:
(a, b, c, d) = s
if a + b + c != 0:
raise ValueError(
"(%d,%d,%d,%d) is not a valid hexagonal Miller "
"index, as the sum of the first three numbers "
"should be zero." % (a, b, c, d))
surfaces[i] = [a, b, d]
ClusterFactory.set_surfaces_layers(self, surfaces, layers)
Hexagonal = HexagonalFactory()
class HexagonalClosedPackedFactory(HexagonalFactory):
"""A factory for creating HCP clusters."""
spacegroup = 194
xtal_name = 'hcp'
atomic_basis = np.array([[0., 0., 0.],
[1. / 3., 2. / 3., .5]])
HexagonalClosedPacked = HexagonalClosedPackedFactory()
class GraphiteFactory(HexagonalFactory):
"""A factory for creating graphite clusters."""
xtal_name = "graphite"
atomic_basis = np.array([[0., 0., 0.],
[1. / 3., 2. / 3., 0.],
[1. / 3., 2. / 3., .5],
[2. / 3., 1. / 3., .5]])
Graphite = GraphiteFactory()
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