def lattice_2_lmpbox(lattice, origin=(0, 0, 0)):
"""
Converts a lattice object to LammpsBox, and calculates the symmetry
operation used.
Args:
lattice (Lattice): Input lattice.
origin: A (3,) array/list of floats setting lower bounds of
simulation box. Default to (0, 0, 0).
Returns:
LammpsBox, SymmOp
"""
a, b, c = lattice.abc
xlo, ylo, zlo = origin
xhi = a + xlo
if lattice.is_orthogonal:
yhi = b + ylo
zhi = c + zlo
tilt = None
rot_matrix = np.eye(3)
else:
m = lattice.matrix
xy = np.dot(m[1], m[0] / a)
yhi = np.sqrt(b**2 - xy**2) + ylo
xz = np.dot(m[2], m[0] / a)
yz = (np.dot(m[1], m[2]) - xy * xz) / (yhi - ylo)
zhi = np.sqrt(c**2 - xz**2 - yz**2) + zlo
tilt = [xy, xz, yz]
rot_matrix = np.linalg.solve(
[[xhi - xlo, 0, 0], [xy, yhi - ylo, 0], [xz, yz, zhi - zlo]], m)
bounds = [[xlo, xhi], [ylo, yhi], [zlo, zhi]]
symmop = SymmOp.from_rotation_and_translation(rot_matrix, origin)
return LammpsBox(bounds, tilt), symmop
def lattice_2_lmpbox(lattice, origin=(0, 0, 0)):
"""
Converts a lattice object to LammpsBox, and calculates the symmetry
operation used.
Args:
lattice (Lattice): Input lattice.
origin: A (3,) array/list of floats setting lower bounds of
simulation box. Default to (0, 0, 0).
Returns:
LammpsBox, SymmOp
"""
a, b, c = lattice.abc
xlo, ylo, zlo = origin
xhi = a + xlo
m = lattice.matrix
xy = np.dot(m[1], m[0] / a)
yhi = np.sqrt(b ** 2 - xy ** 2) + ylo
xz = np.dot(m[2], m[0] / a)
yz = (np.dot(m[1], m[2]) - xy * xz) / (yhi - ylo)
zhi = np.sqrt(c ** 2 - xz ** 2 - yz ** 2) + zlo
tilt = None if lattice.is_orthogonal else [xy, xz, yz]
rot_matrix = np.linalg.solve([[xhi - xlo, 0, 0],
[xy, yhi - ylo, 0],
[xz, yz, zhi - zlo]], m)
bounds = [[xlo, xhi], [ylo, yhi], [zlo, zhi]]
symmop = SymmOp.from_rotation_and_translation(rot_matrix, origin)
return LammpsBox(bounds, tilt), symmop
def from_structure(cls, structure, ff_elements=None, atom_style="charge"):
"""
Simple constructor building LammpsData from a structure without
force field parameters and topologies.
Args:
structure (Structure): Input structure.
ff_elements ([str]): List of strings of elements that must
be present due to force field settings but not
necessarily in the structure. Default to None.
atom_style (str): Choose between "atomic" (neutral) and
"charge" (charged). Default to "charge".
"""
s = structure.get_sorted_structure()
box, symmop = lattice_2_lmpbox(s.lattice)
coords = symmop.operate_multi(s.cart_coords)
site_properties = s.site_properties
if "velocities" in site_properties:
velos = np.array(s.site_properties["velocities"])
rot = SymmOp.from_rotation_and_translation(symmop.rotation_matrix)
rot_velos = rot.operate_multi(velos)
site_properties.update({"velocities": rot_velos})
boxed_s = Structure(box.to_lattice(),
s.species,
coords,
site_properties=site_properties,
coords_are_cartesian=True)
symbols = list(s.symbol_set)
if ff_elements:
symbols.extend(ff_elements)
elements = sorted(Element(el) for el in set(symbols))
mass_info = [tuple([i.symbol] * 2) for i in elements]
ff = ForceField(mass_info)
topo = Topology(boxed_s)
return cls.from_ff_and_topologies(box=box,
ff=ff,
topologies=[topo],
atom_style=atom_style)
def from_structure(cls, structure, ff_elements=None, atom_style="charge"):
"""
Simple constructor building LammpsData from a structure without
force field parameters and topologies.
Args:
structure (Structure): Input structure.
ff_elements ([str]): List of strings of elements that must
be present due to force field settings but not
necessarily in the structure. Default to None.
atom_style (str): Choose between "atomic" (neutral) and
"charge" (charged). Default to "charge".
"""
s = structure.get_sorted_structure()
box, symmop = lattice_2_lmpbox(s.lattice)
coords = symmop.operate_multi(s.cart_coords)
site_properties = s.site_properties
if "velocities" in site_properties:
velos = np.array(s.site_properties["velocities"])
rot = SymmOp.from_rotation_and_translation(symmop.rotation_matrix)
rot_velos = rot.operate_multi(velos)
site_properties.update({"velocities": rot_velos})
boxed_s = Structure(box.to_lattice(), s.species, coords,
site_properties=site_properties,
coords_are_cartesian=True)
symbols = list(s.symbol_set)
if ff_elements:
symbols.extend(ff_elements)
elements = sorted(Element(el) for el in set(symbols))
mass_info = [tuple([i.symbol] * 2) for i in elements]
ff = ForceField(mass_info)
topo = Topology(boxed_s)
return cls.from_ff_and_topologies(box=box, ff=ff, topologies=[topo],
atom_style=atom_style)
def __init__(self, struct, symprec=None, charges=None):
"""
A wrapper around CifFile to write CIF files from pymatgen structures.
Args:
struct (Structure): structure to write
symprec (float): If not none, finds the symmetry of the structure
and writes the cif with symmetry information. Passes symprec
to the SpacegroupAnalyzer
write_magmoms (bool): If True, will write magCIF file. Incompatible
with symprec
"""
format_str = "{:.8f}"
block = OrderedDict()
loops = []
spacegroup = ("P 1", 1)
if symprec is not None:
sf = SpacegroupAnalyzer(struct, symprec)
spacegroup = (sf.get_space_group_symbol(),
sf.get_space_group_number())
# Needs the refined struture when using symprec. This converts
# primitive to conventional structures, the standard for CIF.
struct = sf.get_refined_structure()
latt = struct.lattice
comp = struct.composition
no_oxi_comp = comp.element_composition
block["_symmetry_space_group_name_H-M"] = spacegroup[0]
for cell_attr in ['a', 'b', 'c']:
block["_cell_length_" + cell_attr] = format_str.format(
getattr(latt, cell_attr))
for cell_attr in ['alpha', 'beta', 'gamma']:
block["_cell_angle_" + cell_attr] = format_str.format(
getattr(latt, cell_attr))
block["_symmetry_Int_Tables_number"] = spacegroup[1]
block["_chemical_formula_structural"] = no_oxi_comp.reduced_formula
block["_chemical_formula_sum"] = no_oxi_comp.formula
block["_cell_volume"] = "%.8f" % latt.volume
reduced_comp, fu = no_oxi_comp.get_reduced_composition_and_factor()
block["_cell_formula_units_Z"] = str(int(fu))
if symprec is None:
block["_symmetry_equiv_pos_site_id"] = ["1"]
block["_symmetry_equiv_pos_as_xyz"] = ["x, y, z"]
else:
sf = SpacegroupAnalyzer(struct, symprec)
symmops = []
for op in sf.get_symmetry_operations():
v = op.translation_vector
symmops.append(
SymmOp.from_rotation_and_translation(
op.rotation_matrix, v))
ops = [op.as_xyz_string() for op in symmops]
block["_symmetry_equiv_pos_site_id"] = \
["%d" % i for i in range(1, len(ops) + 1)]
block["_symmetry_equiv_pos_as_xyz"] = ops
loops.append(
["_symmetry_equiv_pos_site_id", "_symmetry_equiv_pos_as_xyz"])
try:
symbol_to_oxinum = OrderedDict([(el.__str__(), float(el.oxi_state))
for el in sorted(comp.elements)])
block["_atom_type_symbol"] = symbol_to_oxinum.keys()
block["_atom_type_oxidation_number"] = symbol_to_oxinum.values()
loops.append(["_atom_type_symbol", "_atom_type_oxidation_number"])
except (TypeError, AttributeError):
symbol_to_oxinum = OrderedDict([(el.symbol, 0)
for el in sorted(comp.elements)])
atom_site_type_symbol = []
atom_site_symmetry_multiplicity = []
atom_site_fract_x = []
atom_site_fract_y = []
atom_site_fract_z = []
atom_site_label = []
atom_site_occupancy = []
atom_site_charge_label = []
count = 1
if symprec is None:
for site in struct:
for sp, occu in sorted(site.species_and_occu.items()):
atom_site_type_symbol.append(sp.__str__())
atom_site_symmetry_multiplicity.append("1")
atom_site_fract_x.append("{0:f}".format(site.a))
atom_site_fract_y.append("{0:f}".format(site.b))
atom_site_fract_z.append("{0:f}".format(site.c))
atom_site_label.append("{}{}".format(sp.symbol, count))
atom_site_occupancy.append(occu.__str__())
count += 1
else:
# The following just presents a deterministic ordering.
unique_sites = [
(sorted(sites,
key=lambda s: tuple([abs(x)
for x in s.frac_coords]))[0],
len(sites))
for sites in sf.get_symmetrized_structure().equivalent_sites
]
for site, mult in sorted(unique_sites,
key=lambda t:
(t[0].species_and_occu.average_electroneg,
-t[1], t[0].a, t[0].b, t[0].c)):
for sp, occu in site.species_and_occu.items():
atom_site_type_symbol.append(sp.__str__())
atom_site_symmetry_multiplicity.append("%d" % mult)
atom_site_fract_x.append("{0:f}".format(site.a))
atom_site_fract_y.append("{0:f}".format(site.b))
atom_site_fract_z.append("{0:f}".format(site.c))
atom_site_label.append("{}{}".format(sp.symbol, count))
atom_site_occupancy.append(occu.__str__())
count += 1
block["_atom_site_type_symbol"] = atom_site_type_symbol
block["_atom_site_label"] = atom_site_label
block["_atom_site_symmetry_multiplicity"] = \
atom_site_symmetry_multiplicity
block["_atom_site_fract_x"] = atom_site_fract_x
block["_atom_site_fract_y"] = atom_site_fract_y
block["_atom_site_fract_z"] = atom_site_fract_z
block["_atom_site_occupancy"] = atom_site_occupancy
block["_atom_site_charge"] = charges
loops.append([
"_atom_site_type_symbol",
"_atom_site_label",
"_atom_site_symmetry_multiplicity",
"_atom_site_fract_x",
"_atom_site_fract_y",
"_atom_site_fract_z",
"_atom_site_occupancy",
"_atom_site_charge",
])
d = OrderedDict()
d[comp.reduced_formula] = CifBlock(block, loops, comp.reduced_formula)
self._cf = CifFile(d)