def get_structure(self, name, elements, a=None, c=None, l=None):
# Check number of elements
if name[:3] in ['fcc', 'hcp']:
if len(elements) != 1:
raise ValueError("Tuple of elements must be of length one")
if name[:3] in ['l12', 'l10'] or name[:2] == 'B2':
if len(elements) != 2:
raise ValueError("Tuple of elements must be of length two")
# Get lattice constants
if a is None:
if name[:2] == 'B2':
a = self.get_lattice_constant_a(name[:2], elements)
elif name[:3] in ['fcc', 'hcp', 'bcc', 'l12', 'l10']:
a = self.get_lattice_constant_a(name[:3], elements)
if c is None:
if name[:3] in ['hcp', 'l10']:
c = self.get_lattice_constant_c(name[:3], elements)
# Get size
if name in ['fcc', 'hcp', 'bcc', 'l12', 'l10', 'B2']:
size = self.properties[name + '_size']
elif name in ['fcc100', 'fcc111', 'hcp0001']:
size = self.properties[name + '_size'][:2] + (l, )
# Make structure
if name == 'fcc':
atoms = FaceCenteredCubic(symbol=elements[0],
size=size,
latticeconstant=a)
elif name == 'hcp':
atoms = HexagonalClosedPacked(symbol=elements[0],
size=size,
directions=[[2, -1, -1, 0],
[0, 1, -1, 0],
[0, 0, 0, 1]],
latticeconstant=(a, c))
elif name == 'bcc':
atoms = BodyCenteredCubic(symbol=elements[0],
size=size,
latticeconstant=a)
elif name == 'B2':
atoms = B2(symbol=elements, size=size, latticeconstant=a)
elif name == 'l12':
atoms = L1_2(symbol=elements, size=size, latticeconstant=a)
elif name == 'l10':
atoms = L1_0(symbol=elements, size=size, latticeconstant=(a, c))
elif name == 'fcc100':
atoms = fcc100(symbol=elements[0], size=size, a=a, vacuum=10.0)
elif name == 'fcc111':
atoms = fcc111(symbol=elements[0],
size=size,
a=a,
vacuum=10.0,
orthogonal=True)
elif name == 'hcp0001':
atoms = hcp0001(symbol=elements[0],
size=size,
a=a,
c=c,
vacuum=10.0,
orthogonal=True)
elif name == 'hcp1010A':
raise ValueError("Structure '%s' not supported" % (name, ))
atoms = None
elif name == 'hcp1010B':
raise ValueError("Structure '%s' not supported" % (name, ))
atoms = None
elif name == 'l12100':
n = (l + 1) / 2
atoms = L1_2(symbol=elements, size=(8, 8, n), latticeconstant=a)
atoms.set_pbc([True, True, False])
# Remove layers
atoms = atoms[atoms.get_positions()[:, 2] > 0.1 * a]
# Set vacuum
atoms.center(axis=2, vacuum=10.0)
elif name == 'l12111':
if l % 3 == 0:
n = l / 3
c = 0
else:
n = l / 3 + 1
c = 3 - l % 3
atoms = L1_2(
symbol=elements,
size=(8, 4, n),
#directions=[[1,-1,0],[1,0,-1],[1,1,1]], latticeconstant=a)
directions=[[1, -1, 0], [1, 1, -2], [1, 1, 1]],
latticeconstant=a)
atoms.set_pbc([True, True, False])
# Wrap positions
scpos = atoms.get_scaled_positions()
scpos[scpos > (1.0 - 1e-12)] = 0.0
atoms.set_scaled_positions(scpos)
# Remove layers
if c > 0:
atoms = atoms[atoms.get_positions()[:, 2] > (c - 0.5) * a /
np.sqrt(3.0)]
# Set vacuum
atoms.center(axis=2, vacuum=10.0)
else:
raise ValueError("Structure '%s' not supported" % (name, ))
return atoms
