def add_snl(self, snl, force_new=False, snlgroup_guess=None): try: self.lock_db() snl_id = self._get_next_snl_id() spstruc = snl.structure.copy() spstruc.remove_oxidation_states() sf = SpacegroupAnalyzer(spstruc, SPACEGROUP_TOLERANCE) sf.get_space_group_operations() sgnum = sf.get_space_group_number() if sf.get_space_group_number() \ else -1 sgsym = sf.get_space_group_symbol() if sf.get_space_group_symbol() \ else 'unknown' sghall = sf.get_hall() if sf.get_hall() else 'unknown' sgxtal = sf.get_crystal_system() if sf.get_crystal_system() \ else 'unknown' sglatt = sf.get_lattice_type() if sf.get_lattice_type() else 'unknown' sgpoint = sf.get_point_group_symbol() mpsnl = MPStructureNL.from_snl(snl, snl_id, sgnum, sgsym, sghall, sgxtal, sglatt, sgpoint) snlgroup, add_new, spec_group = self.add_mpsnl(mpsnl, force_new, snlgroup_guess) self.release_lock() return mpsnl, snlgroup.snlgroup_id, spec_group except: self.release_lock() traceback.print_exc() raise ValueError("Error while adding SNL!")
def add_snl(self, snl, force_new=False, snlgroup_guess=None): try: self.lock_db() snl_id = self._get_next_snl_id() spstruc = snl.structure.copy() spstruc.remove_oxidation_states() sf = SpacegroupAnalyzer(spstruc, SPACEGROUP_TOLERANCE) sf.get_spacegroup() sgnum = sf.get_spacegroup_number() if sf.get_spacegroup_number() \ else -1 sgsym = sf.get_spacegroup_symbol() if sf.get_spacegroup_symbol() \ else 'unknown' sghall = sf.get_hall() if sf.get_hall() else 'unknown' sgxtal = sf.get_crystal_system() if sf.get_crystal_system() \ else 'unknown' sglatt = sf.get_lattice_type() if sf.get_lattice_type( ) else 'unknown' sgpoint = sf.get_point_group() mpsnl = MPStructureNL.from_snl(snl, snl_id, sgnum, sgsym, sghall, sgxtal, sglatt, sgpoint) snlgroup, add_new, spec_group = self.add_mpsnl( mpsnl, force_new, snlgroup_guess) self.release_lock() return mpsnl, snlgroup.snlgroup_id, spec_group except: self.release_lock() traceback.print_exc() raise ValueError("Error while adding SNL!")
def _get_sigmas_options_and_ratio(structure, rotation_axis): rotation_axis = [int(i) for i in rotation_axis] lat_type = ( "c" # assume cubic if no structure specified, just to set initial choices ) ratio = None if structure: sga = SpacegroupAnalyzer(structure) lat_type = sga.get_lattice_type()[ 0] # this should be fixed in pymatgen try: ratio = GrainBoundaryGenerator(structure).get_ratio() except Exception: ratio = None cutoff = 10 if lat_type.lower() == "c": sigmas = GrainBoundaryGenerator.enum_sigma_cubic( cutoff=cutoff, r_axis=rotation_axis) elif lat_type.lower() == "t": sigmas = GrainBoundaryGenerator.enum_sigma_tet( cutoff=cutoff, r_axis=rotation_axis, c2_a2_ratio=ratio) elif lat_type.lower() == "o": sigmas = GrainBoundaryGenerator.enum_sigma_ort( cutoff=cutoff, r_axis=rotation_axis, c2_b2_a2_ratio=ratio) elif lat_type.lower() == "h": sigmas = GrainBoundaryGenerator.enum_sigma_hex( cutoff=cutoff, r_axis=rotation_axis, c2_a2_ratio=ratio) elif lat_type.lower() == "r": sigmas = GrainBoundaryGenerator.enum_sigma_rho( cutoff=cutoff, r_axis=rotation_axis, ratio_alpha=ratio) else: return [], None, ratio options = [] subscript_unicode_map = { 0: "₀", 1: "₁", 2: "₂", 3: "₃", 4: "₄", 5: "₅", 6: "₆", 7: "₇", 8: "₈", 9: "₉", } for sigma in sorted(sigmas.keys()): sigma_label = "Σ{}".format(sigma) for k, v in subscript_unicode_map.items(): sigma_label = sigma_label.replace(str(k), v) options.append({"label": sigma_label, "value": sigma}) return sigmas, options, ratio
def main(): parser = argparse.ArgumentParser() parser.add_argument('-f', '--file', default='POSCAR', type=str, help='path to input file') parser.add_argument('-t', '--tol', default=1e-3, type=float, help='symmetry tolerance (default 1e-3)') parser.add_argument('-o', '--output', default='poscar', help='output file format') args = parser.parse_args() struct = Structure.from_file(args.file) sym = SpacegroupAnalyzer(struct, symprec=args.tol) data = sym.get_symmetry_dataset() print("Initial structure has {} atoms".format(struct.num_sites)) print("\tSpace group number: {}".format(data['number'])) print("\tInternational symbol: {}".format(data['international'])) print("\tLattice type: {}".format(sym.get_lattice_type())) # seekpath conventional cell definition different from spglib std = spglib.refine_cell(sym._cell, symprec=args.tol) seek_data = seekpath.get_path(std) # now remake the structure lattice = seek_data['conv_lattice'] scaled_positions = seek_data['conv_positions'] numbers = seek_data['conv_types'] species = [sym._unique_species[i - 1] for i in numbers] conv = Structure(lattice, species, scaled_positions) conv.get_sorted_structure().to(filename="{}_conv".format(args.file), fmt=args.output) print("Final structure has {} atoms".format(conv.num_sites))
def main(): parser = argparse.ArgumentParser() parser.add_argument('-f', '--file', type=str, default='POSCAR', help='path to input file') parser.add_argument('-t', '--tol', default=1e-3, type=float, help='symmetry tolerance (default 1e-3)') args = parser.parse_args() struct = Structure.from_file(args.file) sym = SpacegroupAnalyzer(struct, symprec=args.tol) data = sym.get_symmetry_dataset() print("Space group number: {}".format(data['number'])) print("International symbol: {}".format(data['international'])) print("Lattice type: {}".format(sym.get_lattice_type()))
def structure_symmetry(): structs, fnames = read_structures() multi_structs(structs, fnames) for struct, fname in zip(structs, fnames): if isinstance(struct, Structure): sa = SpacegroupAnalyzer(struct) print("file name: {}".format(fname)) print("{} : {}".format('Structure Type', 'periodicity')) print("{} : {}".format('Lattice Type', sa.get_lattice_type())) print("{} : {}".format('Space Group ID', sa.get_space_group_number())) print("{} : {}".format('International Symbol', sa.get_space_group_symbol())) print("{} : {}".format('Hall Symbol', sa.get_hall())) sepline() if isinstance(struct, Molecule): print("file name: {}".format(fname)) sa = PointGroupAnalyzer(struct) print("{} : {}".format('Structure Type', 'non-periodicity')) print("{} : {}".format('International Symbol', ast.get_pointgroup())) return True
def main(): parser = argparse.ArgumentParser() parser.add_argument('-f', '--file', default='POSCAR', type=str, help='path to input file') parser.add_argument('-t', '--tol', default=1e-3, type=float, help='symmetry tolerance (default 1e-3)') parser.add_argument('-o', '--output', default='poscar', help='output file format') args = parser.parse_args() struct = Structure.from_file(args.file) sym = SpacegroupAnalyzer(struct, symprec=args.tol) data = sym.get_symmetry_dataset() print('Initial structure has {} atoms'.format(struct.num_sites)) print('\tSpace group number: {}'.format(data['number'])) print('\tInternational symbol: {}'.format(data['international'])) print('\tLattice type: {}'.format(sym.get_lattice_type())) # first standardise the cell using the tolerance we want (seekpath has no # tolerance setting) std = spglib.refine_cell(sym._cell, symprec=args.tol) seek_data = seekpath.get_path(std) transform = seek_data['primitive_transformation_matrix'] # now remake the structure lattice = seek_data['primitive_lattice'] scaled_positions = seek_data['primitive_positions'] numbers = seek_data['primitive_types'] species = [sym._unique_species[i - 1] for i in numbers] prim = Structure(lattice, species, scaled_positions) prim.get_sorted_structure().to(filename='{}_prim'.format(args.file), fmt=args.output) print('Final structure has {} atoms'.format(prim.num_sites)) print('Conv -> Prim transformation matrix:') print('\t' + str(transform).replace('\n', '\n\t'))
class HighSymmKpath(object): """ This class looks for path along high symmetry lines in the Brillouin Zone. It is based on Setyawan, W., & Curtarolo, S. (2010). High-throughput electronic band structure calculations: Challenges and tools. Computational Materials Science, 49(2), 299-312. doi:10.1016/j.commatsci.2010.05.010 The symmetry is determined by spglib through the SpacegroupAnalyzer class Args: structure (Structure): Structure object symprec (float): Tolerance for symmetry finding angle_tolerance (float): Angle tolerance for symmetry finding. """ def __init__(self, structure, symprec=0.01, angle_tolerance=5): self._structure = structure self._sym = SpacegroupAnalyzer(structure, symprec=symprec, angle_tolerance=angle_tolerance) self._prim = self._sym\ .get_primitive_standard_structure(international_monoclinic=False) self._conv = self._sym.get_conventional_standard_structure(international_monoclinic=False) self._prim_rec = self._prim.lattice.reciprocal_lattice self._kpath = None lattice_type = self._sym.get_lattice_type() spg_symbol = self._sym.get_spacegroup_symbol() if lattice_type == "cubic": if "P" in spg_symbol: self._kpath = self.cubic() elif "F" in spg_symbol: self._kpath = self.fcc() elif "I" in spg_symbol: self._kpath = self.bcc() else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "tetragonal": if "P" in spg_symbol: self._kpath = self.tet() elif "I" in spg_symbol: a = self._conv.lattice.abc[0] c = self._conv.lattice.abc[2] if c < a: self._kpath = self.bctet1(c, a) else: self._kpath = self.bctet2(c, a) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "orthorhombic": a = self._conv.lattice.abc[0] b = self._conv.lattice.abc[1] c = self._conv.lattice.abc[2] if "P" in spg_symbol: self._kpath = self.orc() elif "F" in spg_symbol: if 1 / a ** 2 > 1 / b ** 2 + 1 / c ** 2: self._kpath = self.orcf1(a, b, c) elif 1 / a ** 2 < 1 / b ** 2 + 1 / c ** 2: self._kpath = self.orcf2(a, b, c) else: self._kpath = self.orcf3(a, b, c) elif "I" in spg_symbol: self._kpath = self.orci(a, b, c) elif "C" in spg_symbol: self._kpath = self.orcc(a, b, c) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "hexagonal": self._kpath = self.hex() elif lattice_type == "rhombohedral": alpha = self._prim.lattice.lengths_and_angles[1][0] if alpha < 90: self._kpath = self.rhl1(alpha * pi / 180) else: self._kpath = self.rhl2(alpha * pi / 180) elif lattice_type == "monoclinic": a, b, c = self._conv.lattice.abc alpha = self._conv.lattice.lengths_and_angles[1][0] #beta = self._conv.lattice.lengths_and_angles[1][1] if "P" in spg_symbol: self._kpath = self.mcl(b, c, alpha * pi / 180) elif "C" in spg_symbol: kgamma = self._prim_rec.lengths_and_angles[1][2] if kgamma > 90: self._kpath = self.mclc1(a, b, c, alpha * pi / 180) if kgamma == 90: self._kpath = self.mclc2(a, b, c, alpha * pi / 180) if kgamma < 90: if b * cos(alpha * pi / 180) / c\ + b ** 2 * sin(alpha) ** 2 / a ** 2 < 1: self._kpath = self.mclc3(a, b, c, alpha * pi / 180) if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha) ** 2 / a ** 2 == 1: self._kpath = self.mclc4(a, b, c, alpha * pi / 180) if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha) ** 2 / a ** 2 > 1: self._kpath = self.mclc5(a, b, c, alpha * pi / 180) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "triclinic": kalpha = self._prim_rec.lengths_and_angles[1][0] kbeta = self._prim_rec.lengths_and_angles[1][1] kgamma = self._prim_rec.lengths_and_angles[1][2] if kalpha > 90 and kbeta > 90 and kgamma > 90: self._kpath = self.tria() if kalpha < 90 and kbeta < 90 and kgamma < 90: self._kpath = self.trib() if kalpha > 90 and kbeta > 90 and kgamma == 90: self._kpath = self.tria() if kalpha < 90 and kbeta < 90 and kgamma == 90: self._kpath = self.trib() else: warn("Unknown lattice type %s" % lattice_type) @property def structure(self): """ Returns: The standardized primitive structure """ return self._prim @property def kpath(self): """ Returns: The symmetry line path in reciprocal space """ return self._kpath def get_kpoints(self, line_density=20, coords_are_cartesian=True): """ Returns: the kpoints along the paths in cartesian coordinates together with the labels for symmetry points -Wei """ list_k_points = [] sym_point_labels = [] for b in self.kpath['path']: for i in range(1, len(b)): start = np.array(self.kpath['kpoints'][b[i - 1]]) end = np.array(self.kpath['kpoints'][b[i]]) distance = np.linalg.norm( self._prim_rec.get_cartesian_coords(start) - self._prim_rec.get_cartesian_coords(end)) nb = int(ceil(distance * line_density)) sym_point_labels.extend([b[i - 1]] + [''] * (nb - 1) + [b[i]]) list_k_points.extend( [self._prim_rec.get_cartesian_coords(start) + float(i) / float(nb) * (self._prim_rec.get_cartesian_coords(end) - self._prim_rec.get_cartesian_coords(start)) for i in range(0, nb + 1)]) if coords_are_cartesian: return list_k_points, sym_point_labels else: frac_k_points = [self._prim_rec.get_fractional_coords(k) for k in list_k_points] return frac_k_points, sym_point_labels def get_kpath_plot(self, **kwargs): """ Gives the plot (as a matplotlib object) of the symmetry line path in the Brillouin Zone. Returns: `matplotlib` figure. ================ ==================================================== kwargs Meaning ================ ==================================================== title Title of the plot (Default: None). show True to show the figure (default: True). savefig 'abc.png' or 'abc.eps' to save the figure to a file. size_kwargs Dictionary with options passed to fig.set_size_inches example: size_kwargs=dict(w=3, h=4) tight_layout True if to call fig.tight_layout (default: False) ================ ==================================================== """ lines = [[self.kpath['kpoints'][k] for k in p] for p in self.kpath['path']] return plot_brillouin_zone(bz_lattice=self._prim_rec, lines=lines, labels=self.kpath['kpoints'], **kwargs) def cubic(self): self.name = "CUB" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'X': np.array([0.0, 0.5, 0.0]), 'R': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.5, 0.0])} path = [["\Gamma", "X", "M", "\Gamma", "R", "X"], ["M", "R"]] return {'kpoints': kpoints, 'path': path} def fcc(self): self.name = "FCC" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'K': np.array([3.0 / 8.0, 3.0 / 8.0, 3.0 / 4.0]), 'L': np.array([0.5, 0.5, 0.5]), 'U': np.array([5.0 / 8.0, 1.0 / 4.0, 5.0 / 8.0]), 'W': np.array([0.5, 1.0 / 4.0, 3.0 / 4.0]), 'X': np.array([0.5, 0.0, 0.5])} path = [["\Gamma", "X", "W", "K", "\Gamma", "L", "U", "W", "L", "K"], ["U", "X"]] return {'kpoints': kpoints, 'path': path} def bcc(self): self.name = "BCC" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'H': np.array([0.5, -0.5, 0.5]), 'P': np.array([0.25, 0.25, 0.25]), 'N': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "H", "N", "\Gamma", "P", "H"], ["P", "N"]] return {'kpoints': kpoints, 'path': path} def tet(self): self.name = "TET" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.5, 0.0]), 'R': np.array([0.0, 0.5, 0.5]), 'X': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "X", "M", "\Gamma", "Z", "R", "A", "Z"], ["X", "R"], ["M", "A"]] return {'kpoints': kpoints, 'path': path} def bctet1(self, c, a): self.name = "BCT1" eta = (1 + c ** 2 / a ** 2) / 4.0 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'M': np.array([-0.5, 0.5, 0.5]), 'N': np.array([0.0, 0.5, 0.0]), 'P': np.array([0.25, 0.25, 0.25]), 'X': np.array([0.0, 0.0, 0.5]), 'Z': np.array([eta, eta, -eta]), 'Z_1': np.array([-eta, 1 - eta, eta])} path = [["\Gamma", "X", "M", "\Gamma", "Z", "P", "N", "Z_1", "M"], ["X", "P"]] return {'kpoints': kpoints, 'path': path} def bctet2(self, c, a): self.name = "BCT2" eta = (1 + a ** 2 / c ** 2) / 4.0 zeta = a ** 2 / (2 * c ** 2) kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.0, 0.5, 0.0]), 'P': np.array([0.25, 0.25, 0.25]), '\Sigma': np.array([-eta, eta, eta]), '\Sigma_1': np.array([eta, 1 - eta, -eta]), 'X': np.array([0.0, 0.0, 0.5]), 'Y': np.array([-zeta, zeta, 0.5]), 'Y_1': np.array([0.5, 0.5, -zeta]), 'Z': np.array([0.5, 0.5, -0.5])} path = [["\Gamma", "X", "Y", "\Sigma", "\Gamma", "Z", "\Sigma_1", "N", "P", "Y_1", "Z"], ["X", "P"]] return {'kpoints': kpoints, 'path': path} def orc(self): self.name = "ORC" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'R': np.array([0.5, 0.5, 0.5]), 'S': np.array([0.5, 0.5, 0.0]), 'T': np.array([0.0, 0.5, 0.5]), 'U': np.array([0.5, 0.0, 0.5]), 'X': np.array([0.5, 0.0, 0.0]), 'Y': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "X", "S", "Y", "\Gamma", "Z", "U", "R", "T", "Z"], ["Y", "T"], ["U", "X"], ["S", "R"]] return {'kpoints': kpoints, 'path': path} def orcf1(self, a, b, c): self.name = "ORCF1" zeta = (1 + a ** 2 / b ** 2 - a ** 2 / c ** 2) / 4 eta = (1 + a ** 2 / b ** 2 + a ** 2 / c ** 2) / 4 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5 + zeta, zeta]), 'A_1': np.array([0.5, 0.5 - zeta, 1 - zeta]), 'L': np.array([0.5, 0.5, 0.5]), 'T': np.array([1, 0.5, 0.5]), 'X': np.array([0.0, eta, eta]), 'X_1': np.array([1, 1 - eta, 1 - eta]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0])} path = [["\Gamma", "Y", "T", "Z", "\Gamma", "X", "A_1", "Y"], ["T", "X_1"], ["X", "A", "Z"], ["L", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def orcf2(self, a, b, c): self.name = "ORCF2" phi = (1 + c ** 2 / b ** 2 - c ** 2 / a ** 2) / 4 eta = (1 + a ** 2 / b ** 2 - a ** 2 / c ** 2) / 4 delta = (1 + b ** 2 / a ** 2 - b ** 2 / c ** 2) / 4 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'C': np.array([0.5, 0.5 - eta, 1 - eta]), 'C_1': np.array([0.5, 0.5 + eta, eta]), 'D': np.array([0.5 - delta, 0.5, 1 - delta]), 'D_1': np.array([0.5 + delta, 0.5, delta]), 'L': np.array([0.5, 0.5, 0.5]), 'H': np.array([1 - phi, 0.5 - phi, 0.5]), 'H_1': np.array([phi, 0.5 + phi, 0.5]), 'X': np.array([0.0, 0.5, 0.5]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0])} path = [["\Gamma", "Y", "C", "D", "X", "\Gamma", "Z", "D_1", "H", "C"], ["C_1", "Z"], ["X", "H_1"], ["H", "Y"], ["L", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def orcf3(self, a, b, c): self.name = "ORCF3" zeta = (1 + a ** 2 / b ** 2 - a ** 2 / c ** 2) / 4 eta = (1 + a ** 2 / b ** 2 + a ** 2 / c ** 2) / 4 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5 + zeta, zeta]), 'A_1': np.array([0.5, 0.5 - zeta, 1 - zeta]), 'L': np.array([0.5, 0.5, 0.5]), 'T': np.array([1, 0.5, 0.5]), 'X': np.array([0.0, eta, eta]), 'X_1': np.array([1, 1 - eta, 1 - eta]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0])} path = [["\Gamma", "Y", "T", "Z", "\Gamma", "X", "A_1", "Y"], ["X", "A", "Z"], ["L", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def orci(self, a, b, c): self.name = "ORCI" zeta = (1 + a ** 2 / c ** 2) / 4 eta = (1 + b ** 2 / c ** 2) / 4 delta = (b ** 2 - a ** 2) / (4 * c ** 2) mu = (a ** 2 + b ** 2) / (4 * c ** 2) kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([-mu, mu, 0.5 - delta]), 'L_1': np.array([mu, -mu, 0.5 + delta]), 'L_2': np.array([0.5 - delta, 0.5 + delta, -mu]), 'R': np.array([0.0, 0.5, 0.0]), 'S': np.array([0.5, 0.0, 0.0]), 'T': np.array([0.0, 0.0, 0.5]), 'W': np.array([0.25, 0.25, 0.25]), 'X': np.array([-zeta, zeta, zeta]), 'X_1': np.array([zeta, 1 - zeta, -zeta]), 'Y': np.array([eta, -eta, eta]), 'Y_1': np.array([1 - eta, eta, -eta]), 'Z': np.array([0.5, 0.5, -0.5])} path = [["\Gamma", "X", "L", "T", "W", "R", "X_1", "Z", "\Gamma", "Y", "S", "W"], ["L_1", "Y"], ["Y_1", "Z"]] return {'kpoints': kpoints, 'path': path} def orcc(self, a, b, c): self.name = "ORCC" zeta = (1 + a ** 2 / b ** 2) / 4 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([zeta, zeta, 0.5]), 'A_1': np.array([-zeta, 1 - zeta, 0.5]), 'R': np.array([0.0, 0.5, 0.5]), 'S': np.array([0.0, 0.5, 0.0]), 'T': np.array([-0.5, 0.5, 0.5]), 'X': np.array([zeta, zeta, 0.0]), 'X_1': np.array([-zeta, 1 - zeta, 0.0]), 'Y': np.array([-0.5, 0.5, 0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "X", "S", "R", "A", "Z", "\Gamma", "Y", "X_1", "A_1", "T", "Y"], ["Z", "T"]] return {'kpoints': kpoints, 'path': path} def hex(self): self.name = "HEX" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.0, 0.0, 0.5]), 'H': np.array([1.0 / 3.0, 1.0 / 3.0, 0.5]), 'K': np.array([1.0 / 3.0, 1.0 / 3.0, 0.0]), 'L': np.array([0.5, 0.0, 0.5]), 'M': np.array([0.5, 0.0, 0.0])} path = [["\Gamma", "M", "K", "\Gamma", "A", "L", "H", "A"], ["L", "M"], ["K", "H"]] return {'kpoints': kpoints, 'path': path} def rhl1(self, alpha): self.name = "RHL1" eta = (1 + 4 * cos(alpha)) / (2 + 4 * cos(alpha)) nu = 3.0 / 4.0 - eta / 2.0 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'B': np.array([eta, 0.5, 1.0 - eta]), 'B_1': np.array([1.0 / 2.0, 1.0 - eta, eta - 1.0]), 'F': np.array([0.5, 0.5, 0.0]), 'L': np.array([0.5, 0.0, 0.0]), 'L_1': np.array([0.0, 0.0, -0.5]), 'P': np.array([eta, nu, nu]), 'P_1': np.array([1.0 - nu, 1.0 - nu, 1.0 - eta]), 'P_2': np.array([nu, nu, eta - 1.0]), 'Q': np.array([1.0 - nu, nu, 0.0]), 'X': np.array([nu, 0.0, -nu]), 'Z': np.array([0.5, 0.5, 0.5])} path = [["\Gamma", "L", "B_1"], ["B", "Z", "\Gamma", "X"], ["Q", "F", "P_1", "Z"], ["L", "P"]] return {'kpoints': kpoints, 'path': path} def rhl2(self, alpha): self.name = "RHL2" eta = 1 / (2 * tan(alpha / 2.0) ** 2) nu = 3.0 / 4.0 - eta / 2.0 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([0.5, -0.5, 0.0]), 'L': np.array([0.5, 0.0, 0.0]), 'P': np.array([1 - nu, -nu, 1 - nu]), 'P_1': np.array([nu, nu - 1.0, nu - 1.0]), 'Q': np.array([eta, eta, eta]), 'Q_1': np.array([1.0 - eta, -eta, -eta]), 'Z': np.array([0.5, -0.5, 0.5])} path = [["\Gamma", "P", "Z", "Q", "\Gamma", "F", "P_1", "Q_1", "L", "Z"]] return {'kpoints': kpoints, 'path': path} def mcl(self, b, c, beta): self.name = "MCL" eta = (1 - b * cos(beta) / c) / (2 * sin(beta) ** 2) nu = 0.5 - eta * c * cos(beta) / b kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5, 0.0]), 'C': np.array([0.0, 0.5, 0.5]), 'D': np.array([0.5, 0.0, 0.5]), 'D_1': np.array([0.5, 0.5, -0.5]), 'E': np.array([0.5, 0.5, 0.5]), 'H': np.array([0.0, eta, 1.0 - nu]), 'H_1': np.array([0.0, 1.0 - eta, nu]), 'H_2': np.array([0.0, eta, -nu]), 'M': np.array([0.5, eta, 1.0 - nu]), 'M_1': np.array([0.5, 1 - eta, nu]), 'M_2': np.array([0.5, 1 - eta, nu]), 'X': np.array([0.0, 0.5, 0.0]), 'Y': np.array([0.0, 0.0, 0.5]), 'Y_1': np.array([0.0, 0.0, -0.5]), 'Z': np.array([0.5, 0.0, 0.0])} path = [["\Gamma", "Y", "H", "C", "E", "M_1", "A", "X", "H_1"], ["M", "D", "Z"], ["Y", "D"]] return {'kpoints': kpoints, 'path': path} def mclc1(self, a, b, c, alpha): self.name = "MCLC1" zeta = (2 - b * cos(alpha) / c) / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b psi = 0.75 - a ** 2 / (4 * b ** 2 * sin(alpha) ** 2) phi = psi + (0.75 - psi) * b * cos(alpha) / c kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'F': np.array([1 - zeta, 1 - zeta, 1 - eta]), 'F_1': np.array([zeta, zeta, eta]), 'F_2': np.array([-zeta, -zeta, 1 - eta]), #'F_3': np.array([1 - zeta, -zeta, 1 - eta]), 'I': np.array([phi, 1 - phi, 0.5]), 'I_1': np.array([1 - phi, phi - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'X': np.array([1 - psi, psi - 1, 0.0]), 'X_1': np.array([psi, 1 - psi, 0.0]), 'X_2': np.array([psi - 1, -psi, 0.0]), 'Y': np.array([0.5, 0.5, 0.0]), 'Y_1': np.array([-0.5, -0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "F_1"], ["Y", "X_1"], ["X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc2(self, a, b, c, alpha): self.name = "MCLC2" zeta = (2 - b * cos(alpha) / c) / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b psi = 0.75 - a ** 2 / (4 * b ** 2 * sin(alpha) ** 2) phi = psi + (0.75 - psi) * b * cos(alpha) / c kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'F': np.array([1 - zeta, 1 - zeta, 1 - eta]), 'F_1': np.array([zeta, zeta, eta]), 'F_2': np.array([-zeta, -zeta, 1 - eta]), 'F_3': np.array([1 - zeta, -zeta, 1 - eta]), 'I': np.array([phi, 1 - phi, 0.5]), 'I_1': np.array([1 - phi, phi - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'X': np.array([1 - psi, psi - 1, 0.0]), 'X_1': np.array([psi, 1 - psi, 0.0]), 'X_2': np.array([psi - 1, -psi, 0.0]), 'Y': np.array([0.5, 0.5, 0.0]), 'Y_1': np.array([-0.5, -0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "F_1"], ["N", "\Gamma", "M"]] return {'kpoints': kpoints, 'path': path} def mclc3(self, a, b, c, alpha): self.name = "MCLC3" mu = (1 + b ** 2 / a ** 2) / 4.0 delta = b * c * cos(alpha) / (2 * a ** 2) zeta = mu - 0.25 + (1 - b * cos(alpha) / c)\ / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b phi = 1 + zeta - 2 * mu psi = eta - 2 * delta kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([1 - phi, 1 - phi, 1 - psi]), 'F_1': np.array([phi, phi - 1, psi]), 'F_2': np.array([1 - phi, -phi, 1 - psi]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([0.5, -0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "Y", "F", "H", "Z", "I", "F_1"], ["H_1", "Y_1", "X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc4(self, a, b, c, alpha): self.name = "MCLC4" mu = (1 + b ** 2 / a ** 2) / 4.0 delta = b * c * cos(alpha) / (2 * a ** 2) zeta = mu - 0.25 + (1 - b * cos(alpha) / c)\ / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b phi = 1 + zeta - 2 * mu psi = eta - 2 * delta kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([1 - phi, 1 - phi, 1 - psi]), 'F_1': np.array([phi, phi - 1, psi]), 'F_2': np.array([1 - phi, -phi, 1 - psi]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([0.5, -0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "Y", "F", "H", "Z", "I"], ["H_1", "Y_1", "X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc5(self, a, b, c, alpha): self.name = "MCLC5" zeta = (b ** 2 / a ** 2 + (1 - b * cos(alpha) / c) / sin(alpha) ** 2) / 4 eta = 0.5 + 2 * zeta * c * cos(alpha) / b mu = eta / 2 + b ** 2 / (4 * a ** 2) \ - b * c * cos(alpha) / (2 * a ** 2) nu = 2 * mu - zeta rho = 1 - zeta * a ** 2 / b ** 2 omega = (4 * nu - 1 - b ** 2 * sin(alpha) ** 2 / a ** 2)\ * c / (2 * b * cos(alpha)) delta = zeta * c * cos(alpha) / b + omega / 2 - 0.25 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([nu, nu, omega]), 'F_1': np.array([1 - nu, 1 - nu, 1 - omega]), 'F_2': np.array([nu, nu - 1, omega]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([rho, 1 - rho, 0.5]), 'I_1': np.array([1 - rho, rho - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "H", "F_1"], ["H_1", "Y_1", "X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def tria(self): self.name = "TRI1a" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([0.5, 0.5, 0.0]), 'M': np.array([0.0, 0.5, 0.5]), 'N': np.array([0.5, 0.0, 0.5]), 'R': np.array([0.5, 0.5, 0.5]), 'X': np.array([0.5, 0.0, 0.0]), 'Y': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["X", "\Gamma", "Y"], ["L", "\Gamma", "Z"], ["N", "\Gamma", "M"], ["R", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def trib(self): self.name = "TRI1b" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([0.5, -0.5, 0.0]), 'M': np.array([0.0, 0.0, 0.5]), 'N': np.array([-0.5, -0.5, 0.5]), 'R': np.array([0.0, -0.5, 0.5]), 'X': np.array([0.0, -0.5, 0.0]), 'Y': np.array([0.5, 0.0, 0.0]), 'Z': np.array([-0.5, 0.0, 0.5])} path = [["X", "\Gamma", "Y"], ["L", "\Gamma", "Z"], ["N", "\Gamma", "M"], ["R", "\Gamma"]] return {'kpoints': kpoints, 'path': path}
def update_contents(self, new_store_contents, symprec, angle_tolerance): try: # input sanitation symprec = float(literal_eval(str(symprec))) angle_tolerance = float(literal_eval(str(angle_tolerance))) except: raise PreventUpdate struct_or_mol = self.from_data(new_store_contents) if not isinstance(struct_or_mol, Structure): return html.Div( "Can only analyze symmetry of crystal structures at present.") sga = SpacegroupAnalyzer(struct_or_mol, symprec=symprec, angle_tolerance=angle_tolerance) try: data = {} data["Crystal System"] = sga.get_crystal_system().title() data["Lattice System"] = sga.get_lattice_type().title() data["Hall Number"] = sga.get_hall() data["International Number"] = sga.get_space_group_number() data["Symbol"] = unicodeify_spacegroup( sga.get_space_group_symbol()) data["Point Group"] = unicodeify_spacegroup( sga.get_point_group_symbol()) sym_struct = sga.get_symmetrized_structure() except: return html.Span( f"Failed to calculate symmetry with this combination of " f"symmetry-finding ({symprec}) and angle tolerances ({angle_tolerance})." ) datalist = get_data_list(data) wyckoff_contents = [] wyckoff_data = sorted( zip(sym_struct.wyckoff_symbols, sym_struct.equivalent_sites), key=lambda x: "".join(filter(lambda w: w.isalpha(), x[0])), ) for symbol, equiv_sites in wyckoff_data: wyckoff_contents.append( html.Label( f"{symbol}, {unicodeify_species(equiv_sites[0].species_string)}", className="mpc-label", )) site_data = [( pretty_frac_format(site.frac_coords[0]), pretty_frac_format(site.frac_coords[1]), pretty_frac_format(site.frac_coords[2]), ) for site in equiv_sites] wyckoff_contents.append(get_table(site_data)) return Columns([ Column([H5("Overview"), datalist]), Column([H5("Wyckoff Positions"), html.Div(wyckoff_contents)]), ])
def update_contents(data, symprec, angle_tolerance): if not data: return html.Div() struct = self.from_data(data) if not isinstance(struct, Structure): return html.Div( "Can only analyze symmetry of crystal structures at present." ) kwargs = self.reconstruct_kwargs_from_state( callback_context.inputs) symprec = kwargs["symprec"] angle_tolerance = kwargs["angle_tolerance"] if symprec <= 0: return html.Span( f"Please use a positive symmetry-finding tolerance (currently {symprec})." ) sga = SpacegroupAnalyzer(struct, symprec=symprec, angle_tolerance=angle_tolerance) try: data = dict() data["Crystal System"] = sga.get_crystal_system().title() data["Lattice System"] = sga.get_lattice_type().title() data["Hall Number"] = sga.get_hall() data["International Number"] = sga.get_space_group_number() data["Symbol"] = unicodeify_spacegroup( sga.get_space_group_symbol()) data["Point Group"] = unicodeify_spacegroup( sga.get_point_group_symbol()) sym_struct = sga.get_symmetrized_structure() except Exception: return html.Span( f"Failed to calculate symmetry with this combination of " f"symmetry-finding ({symprec}) and angle tolerances ({angle_tolerance})." ) datalist = get_data_list(data) wyckoff_contents = [] wyckoff_data = sorted( zip(sym_struct.wyckoff_symbols, sym_struct.equivalent_sites), key=lambda x: "".join(filter(lambda w: w.isalpha(), x[0])), ) for symbol, equiv_sites in wyckoff_data: wyckoff_contents.append( html.Label( f"{symbol}, {unicodeify_species(equiv_sites[0].species_string)}", className="mpc-label", )) site_data = [( self.pretty_frac_format(site.frac_coords[0]), self.pretty_frac_format(site.frac_coords[1]), self.pretty_frac_format(site.frac_coords[2]), ) for site in equiv_sites] wyckoff_contents.append(get_table(site_data)) return Columns([ Column([H5("Overview"), datalist]), Column([H5("Wyckoff Positions"), html.Div(wyckoff_contents)]), ])
def calc_shiftk(self, symprec=0.01, angle_tolerance=5): """ Find the values of shiftk and nshiftk appropriate for the sampling of the Brillouin zone. Returns Suggested value of shiftk .. note: When the primitive vectors of the lattice do NOT form a FCC or a BCC lattice, the usual (shifted) Monkhorst-Pack grids are formed by using nshiftk=1 and shiftk 0.5 0.5 0.5 . This is often the preferred k point sampling. For a non-shifted Monkhorst-Pack grid, use nshiftk=1 and shiftk 0.0 0.0 0.0 , but there is little reason to do that. 2) When the primitive vectors of the lattice form a FCC lattice, with rprim 0.0 0.5 0.5 0.5 0.0 0.5 0.5 0.5 0.0 the (very efficient) usual Monkhorst-Pack sampling will be generated by using nshiftk= 4 and shiftk 0.5 0.5 0.5 0.5 0.0 0.0 0.0 0.5 0.0 0.0 0.0 0.5 3) When the primitive vectors of the lattice form a BCC lattice, with rprim -0.5 0.5 0.5 0.5 -0.5 0.5 0.5 0.5 -0.5 the usual Monkhorst-Pack sampling will be generated by using nshiftk= 2 and shiftk 0.25 0.25 0.25 -0.25 -0.25 -0.25 However, the simple sampling nshiftk=1 and shiftk 0.5 0.5 0.5 is excellent. 4) For hexagonal lattices with hexagonal axes, e.g. rprim 1.0 0.0 0.0 -0.5 sqrt(3)/2 0.0 0.0 0.0 1.0 one can use nshiftk= 1 and shiftk 0.0 0.0 0.5 In rhombohedral axes, e.g. using angdeg 3*60., this corresponds to shiftk 0.5 0.5 0.5, to keep the shift along the symmetry axis. """ # Find lattice type. sym = SpacegroupAnalyzer(self, symprec=symprec, angle_tolerance=angle_tolerance) lattice_type = sym.get_lattice_type() spg_symbol = sym.get_spacegroup_symbol() # Generate the appropriate set of shifts. shiftk = None if lattice_type == "cubic": if "F" in spg_symbol: # FCC shiftk = [0.5, 0.5, 0.5, 0.5, 0.0, 0.0, 0.0, 0.5, 0.0, 0.0, 0.0, 0.5] elif "I" in spg_symbol: # BCC shiftk = [0.25, 0.25, 0.25, -0.25, -0.25, -0.25] #shiftk = [0.5, 0.5, 05]) elif lattice_type == "hexagonal": # Find the hexagonal axis and set the shift along it. for i, angle in enumerate(self.lattice.angles): if abs(angle - 120) < 1.0: j = (i + 1) % 3 k = (i + 2) % 3 hex_ax = [ax for ax in range(3) if ax not in [j,k]][0] break else: raise ValueError("Cannot find hexagonal axis") shiftk = [0.0, 0.0, 0.0] shiftk[hex_ax] = 0.5 if shiftk is None: # Use default value. shiftk = [0.5, 0.5, 0.5] return np.reshape(shiftk, (-1,3))
class HighSymmKpath: """ This class looks for path along high symmetry lines in the Brillouin Zone. It is based on Setyawan, W., & Curtarolo, S. (2010). High-throughput electronic band structure calculations: Challenges and tools. Computational Materials Science, 49(2), 299-312. doi:10.1016/j.commatsci.2010.05.010 It should be used with primitive structures that comply with the definition from the paper. The symmetry is determined by spglib through the SpacegroupAnalyzer class. The analyzer can be used to produce the correct primitive structure (method get_primitive_standard_structure(international_monoclinic=False)). A warning will signal possible compatibility problems with the given structure. Args: structure (Structure): Structure object symprec (float): Tolerance for symmetry finding angle_tolerance (float): Angle tolerance for symmetry finding. atol (float): Absolute tolerance used to compare the input structure with the one expected as primitive standard. A warning will be issued if the lattices don't match. """ def __init__(self, structure, symprec=0.01, angle_tolerance=5, atol=1e-8): self._structure = structure self._sym = SpacegroupAnalyzer(structure, symprec=symprec, angle_tolerance=angle_tolerance) self._prim = self._sym \ .get_primitive_standard_structure(international_monoclinic=False) self._conv = self._sym.get_conventional_standard_structure( international_monoclinic=False) self._prim_rec = self._prim.lattice.reciprocal_lattice self._kpath = None # Note: this warning will be issued for space groups 38-41, since the primitive cell must be # reformatted to match Setyawan/Curtarolo convention in order to work with the current k-path # generation scheme. if not np.allclose(self._structure.lattice.matrix, self._prim.lattice.matrix, atol=atol): warnings.warn( "The input structure does not match the expected standard primitive! " "The path can be incorrect. Use at your own risk.") lattice_type = self._sym.get_lattice_type() spg_symbol = self._sym.get_space_group_symbol() if lattice_type == "cubic": if "P" in spg_symbol: self._kpath = self.cubic() elif "F" in spg_symbol: self._kpath = self.fcc() elif "I" in spg_symbol: self._kpath = self.bcc() else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "tetragonal": if "P" in spg_symbol: self._kpath = self.tet() elif "I" in spg_symbol: a = self._conv.lattice.abc[0] c = self._conv.lattice.abc[2] if c < a: self._kpath = self.bctet1(c, a) else: self._kpath = self.bctet2(c, a) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "orthorhombic": a = self._conv.lattice.abc[0] b = self._conv.lattice.abc[1] c = self._conv.lattice.abc[2] if "P" in spg_symbol: self._kpath = self.orc() elif "F" in spg_symbol: if 1 / a**2 > 1 / b**2 + 1 / c**2: self._kpath = self.orcf1(a, b, c) elif 1 / a**2 < 1 / b**2 + 1 / c**2: self._kpath = self.orcf2(a, b, c) else: self._kpath = self.orcf3(a, b, c) elif "I" in spg_symbol: self._kpath = self.orci(a, b, c) elif "C" in spg_symbol or "A" in spg_symbol: self._kpath = self.orcc(a, b, c) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "hexagonal": self._kpath = self.hex() elif lattice_type == "rhombohedral": alpha = self._prim.lattice.lengths_and_angles[1][0] if alpha < 90: self._kpath = self.rhl1(alpha * pi / 180) else: self._kpath = self.rhl2(alpha * pi / 180) elif lattice_type == "monoclinic": a, b, c = self._conv.lattice.abc alpha = self._conv.lattice.lengths_and_angles[1][0] # beta = self._conv.lattice.lengths_and_angles[1][1] if "P" in spg_symbol: self._kpath = self.mcl(b, c, alpha * pi / 180) elif "C" in spg_symbol: kgamma = self._prim_rec.lengths_and_angles[1][2] if kgamma > 90: self._kpath = self.mclc1(a, b, c, alpha * pi / 180) if kgamma == 90: self._kpath = self.mclc2(a, b, c, alpha * pi / 180) if kgamma < 90: if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha * pi / 180) ** 2 / a ** 2 < 1: self._kpath = self.mclc3(a, b, c, alpha * pi / 180) if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha * pi / 180) ** 2 / a ** 2 == 1: self._kpath = self.mclc4(a, b, c, alpha * pi / 180) if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha * pi / 180) ** 2 / a ** 2 > 1: self._kpath = self.mclc5(a, b, c, alpha * pi / 180) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "triclinic": kalpha = self._prim_rec.lengths_and_angles[1][0] kbeta = self._prim_rec.lengths_and_angles[1][1] kgamma = self._prim_rec.lengths_and_angles[1][2] if kalpha > 90 and kbeta > 90 and kgamma > 90: self._kpath = self.tria() if kalpha < 90 and kbeta < 90 and kgamma < 90: self._kpath = self.trib() if kalpha > 90 and kbeta > 90 and kgamma == 90: self._kpath = self.tria() if kalpha < 90 and kbeta < 90 and kgamma == 90: self._kpath = self.trib() else: warn("Unknown lattice type %s" % lattice_type) @property def structure(self): """ Returns: The standardized primitive structure """ return self._prim @property def conventional(self): """ Returns: The conventional cell structure """ return self._conv @property def prim(self): """ Returns: The primitive cell structure """ return self._prim @property def prim_rec(self): """ Returns: The primitive reciprocal cell structure """ return self._prim_rec @property def kpath(self): """ Returns: The symmetry line path in reciprocal space """ return self._kpath def get_kpoints(self, line_density=20, coords_are_cartesian=True): """ Returns: the kpoints along the paths in cartesian coordinates together with the labels for symmetry points -Wei """ list_k_points = [] sym_point_labels = [] for b in self.kpath['path']: for i in range(1, len(b)): start = np.array(self.kpath['kpoints'][b[i - 1]]) end = np.array(self.kpath['kpoints'][b[i]]) distance = np.linalg.norm( self._prim_rec.get_cartesian_coords(start) - self._prim_rec.get_cartesian_coords(end)) nb = int(ceil(distance * line_density)) sym_point_labels.extend([b[i - 1]] + [''] * (nb - 1) + [b[i]]) list_k_points.extend([ self._prim_rec.get_cartesian_coords(start) + float(i) / float(nb) * (self._prim_rec.get_cartesian_coords(end) - self._prim_rec.get_cartesian_coords(start)) for i in range(0, nb + 1) ]) if coords_are_cartesian: return list_k_points, sym_point_labels else: frac_k_points = [ self._prim_rec.get_fractional_coords(k) for k in list_k_points ] return frac_k_points, sym_point_labels def cubic(self): self.name = "CUB" kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'X': np.array([0.0, 0.5, 0.0]), 'R': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.5, 0.0]) } path = [["\\Gamma", "X", "M", "\\Gamma", "R", "X"], ["M", "R"]] return {'kpoints': kpoints, 'path': path} def fcc(self): self.name = "FCC" kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'K': np.array([3.0 / 8.0, 3.0 / 8.0, 3.0 / 4.0]), 'L': np.array([0.5, 0.5, 0.5]), 'U': np.array([5.0 / 8.0, 1.0 / 4.0, 5.0 / 8.0]), 'W': np.array([0.5, 1.0 / 4.0, 3.0 / 4.0]), 'X': np.array([0.5, 0.0, 0.5]) } path = [["\\Gamma", "X", "W", "K", "\\Gamma", "L", "U", "W", "L", "K"], ["U", "X"]] return {'kpoints': kpoints, 'path': path} def bcc(self): self.name = "BCC" kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'H': np.array([0.5, -0.5, 0.5]), 'P': np.array([0.25, 0.25, 0.25]), 'N': np.array([0.0, 0.0, 0.5]) } path = [["\\Gamma", "H", "N", "\\Gamma", "P", "H"], ["P", "N"]] return {'kpoints': kpoints, 'path': path} def tet(self): self.name = "TET" kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.5, 0.0]), 'R': np.array([0.0, 0.5, 0.5]), 'X': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\\Gamma", "X", "M", "\\Gamma", "Z", "R", "A", "Z"], ["X", "R"], ["M", "A"]] return {'kpoints': kpoints, 'path': path} def bctet1(self, c, a): self.name = "BCT1" eta = (1 + c**2 / a**2) / 4.0 kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'M': np.array([-0.5, 0.5, 0.5]), 'N': np.array([0.0, 0.5, 0.0]), 'P': np.array([0.25, 0.25, 0.25]), 'X': np.array([0.0, 0.0, 0.5]), 'Z': np.array([eta, eta, -eta]), 'Z_1': np.array([-eta, 1 - eta, eta]) } path = [["\\Gamma", "X", "M", "\\Gamma", "Z", "P", "N", "Z_1", "M"], ["X", "P"]] return {'kpoints': kpoints, 'path': path} def bctet2(self, c, a): self.name = "BCT2" eta = (1 + a**2 / c**2) / 4.0 zeta = a**2 / (2 * c**2) kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.0, 0.5, 0.0]), 'P': np.array([0.25, 0.25, 0.25]), '\\Sigma': np.array([-eta, eta, eta]), '\\Sigma_1': np.array([eta, 1 - eta, -eta]), 'X': np.array([0.0, 0.0, 0.5]), 'Y': np.array([-zeta, zeta, 0.5]), 'Y_1': np.array([0.5, 0.5, -zeta]), 'Z': np.array([0.5, 0.5, -0.5]) } path = [[ "\\Gamma", "X", "Y", "\\Sigma", "\\Gamma", "Z", "\\Sigma_1", "N", "P", "Y_1", "Z" ], ["X", "P"]] return {'kpoints': kpoints, 'path': path} def orc(self): self.name = "ORC" kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'R': np.array([0.5, 0.5, 0.5]), 'S': np.array([0.5, 0.5, 0.0]), 'T': np.array([0.0, 0.5, 0.5]), 'U': np.array([0.5, 0.0, 0.5]), 'X': np.array([0.5, 0.0, 0.0]), 'Y': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\\Gamma", "X", "S", "Y", "\\Gamma", "Z", "U", "R", "T", "Z"], ["Y", "T"], ["U", "X"], ["S", "R"]] return {'kpoints': kpoints, 'path': path} def orcf1(self, a, b, c): self.name = "ORCF1" zeta = (1 + a**2 / b**2 - a**2 / c**2) / 4 eta = (1 + a**2 / b**2 + a**2 / c**2) / 4 kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5 + zeta, zeta]), 'A_1': np.array([0.5, 0.5 - zeta, 1 - zeta]), 'L': np.array([0.5, 0.5, 0.5]), 'T': np.array([1, 0.5, 0.5]), 'X': np.array([0.0, eta, eta]), 'X_1': np.array([1, 1 - eta, 1 - eta]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0]) } path = [["\\Gamma", "Y", "T", "Z", "\\Gamma", "X", "A_1", "Y"], ["T", "X_1"], ["X", "A", "Z"], ["L", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def orcf2(self, a, b, c): self.name = "ORCF2" phi = (1 + c**2 / b**2 - c**2 / a**2) / 4 eta = (1 + a**2 / b**2 - a**2 / c**2) / 4 delta = (1 + b**2 / a**2 - b**2 / c**2) / 4 kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'C': np.array([0.5, 0.5 - eta, 1 - eta]), 'C_1': np.array([0.5, 0.5 + eta, eta]), 'D': np.array([0.5 - delta, 0.5, 1 - delta]), 'D_1': np.array([0.5 + delta, 0.5, delta]), 'L': np.array([0.5, 0.5, 0.5]), 'H': np.array([1 - phi, 0.5 - phi, 0.5]), 'H_1': np.array([phi, 0.5 + phi, 0.5]), 'X': np.array([0.0, 0.5, 0.5]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0]) } path = [[ "\\Gamma", "Y", "C", "D", "X", "\\Gamma", "Z", "D_1", "H", "C" ], ["C_1", "Z"], ["X", "H_1"], ["H", "Y"], ["L", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def orcf3(self, a, b, c): self.name = "ORCF3" zeta = (1 + a**2 / b**2 - a**2 / c**2) / 4 eta = (1 + a**2 / b**2 + a**2 / c**2) / 4 kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5 + zeta, zeta]), 'A_1': np.array([0.5, 0.5 - zeta, 1 - zeta]), 'L': np.array([0.5, 0.5, 0.5]), 'T': np.array([1, 0.5, 0.5]), 'X': np.array([0.0, eta, eta]), 'X_1': np.array([1, 1 - eta, 1 - eta]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0]) } path = [["\\Gamma", "Y", "T", "Z", "\\Gamma", "X", "A_1", "Y"], ["X", "A", "Z"], ["L", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def orci(self, a, b, c): self.name = "ORCI" zeta = (1 + a**2 / c**2) / 4 eta = (1 + b**2 / c**2) / 4 delta = (b**2 - a**2) / (4 * c**2) mu = (a**2 + b**2) / (4 * c**2) kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([-mu, mu, 0.5 - delta]), 'L_1': np.array([mu, -mu, 0.5 + delta]), 'L_2': np.array([0.5 - delta, 0.5 + delta, -mu]), 'R': np.array([0.0, 0.5, 0.0]), 'S': np.array([0.5, 0.0, 0.0]), 'T': np.array([0.0, 0.0, 0.5]), 'W': np.array([0.25, 0.25, 0.25]), 'X': np.array([-zeta, zeta, zeta]), 'X_1': np.array([zeta, 1 - zeta, -zeta]), 'Y': np.array([eta, -eta, eta]), 'Y_1': np.array([1 - eta, eta, -eta]), 'Z': np.array([0.5, 0.5, -0.5]) } path = [[ "\\Gamma", "X", "L", "T", "W", "R", "X_1", "Z", "\\Gamma", "Y", "S", "W" ], ["L_1", "Y"], ["Y_1", "Z"]] return {'kpoints': kpoints, 'path': path} def orcc(self, a, b, c): self.name = "ORCC" zeta = (1 + a**2 / b**2) / 4 kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([zeta, zeta, 0.5]), 'A_1': np.array([-zeta, 1 - zeta, 0.5]), 'R': np.array([0.0, 0.5, 0.5]), 'S': np.array([0.0, 0.5, 0.0]), 'T': np.array([-0.5, 0.5, 0.5]), 'X': np.array([zeta, zeta, 0.0]), 'X_1': np.array([-zeta, 1 - zeta, 0.0]), 'Y': np.array([-0.5, 0.5, 0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [[ "\\Gamma", "X", "S", "R", "A", "Z", "\\Gamma", "Y", "X_1", "A_1", "T", "Y" ], ["Z", "T"]] return {'kpoints': kpoints, 'path': path} def hex(self): self.name = "HEX" kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.0, 0.0, 0.5]), 'H': np.array([1.0 / 3.0, 1.0 / 3.0, 0.5]), 'K': np.array([1.0 / 3.0, 1.0 / 3.0, 0.0]), 'L': np.array([0.5, 0.0, 0.5]), 'M': np.array([0.5, 0.0, 0.0]) } path = [["\\Gamma", "M", "K", "\\Gamma", "A", "L", "H", "A"], ["L", "M"], ["K", "H"]] return {'kpoints': kpoints, 'path': path} def rhl1(self, alpha): self.name = "RHL1" eta = (1 + 4 * cos(alpha)) / (2 + 4 * cos(alpha)) nu = 3.0 / 4.0 - eta / 2.0 kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'B': np.array([eta, 0.5, 1.0 - eta]), 'B_1': np.array([1.0 / 2.0, 1.0 - eta, eta - 1.0]), 'F': np.array([0.5, 0.5, 0.0]), 'L': np.array([0.5, 0.0, 0.0]), 'L_1': np.array([0.0, 0.0, -0.5]), 'P': np.array([eta, nu, nu]), 'P_1': np.array([1.0 - nu, 1.0 - nu, 1.0 - eta]), 'P_2': np.array([nu, nu, eta - 1.0]), 'Q': np.array([1.0 - nu, nu, 0.0]), 'X': np.array([nu, 0.0, -nu]), 'Z': np.array([0.5, 0.5, 0.5]) } path = [["\\Gamma", "L", "B_1"], ["B", "Z", "\\Gamma", "X"], ["Q", "F", "P_1", "Z"], ["L", "P"]] return {'kpoints': kpoints, 'path': path} def rhl2(self, alpha): self.name = "RHL2" eta = 1 / (2 * tan(alpha / 2.0)**2) nu = 3.0 / 4.0 - eta / 2.0 kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([0.5, -0.5, 0.0]), 'L': np.array([0.5, 0.0, 0.0]), 'P': np.array([1 - nu, -nu, 1 - nu]), 'P_1': np.array([nu, nu - 1.0, nu - 1.0]), 'Q': np.array([eta, eta, eta]), 'Q_1': np.array([1.0 - eta, -eta, -eta]), 'Z': np.array([0.5, -0.5, 0.5]) } path = [[ "\\Gamma", "P", "Z", "Q", "\\Gamma", "F", "P_1", "Q_1", "L", "Z" ]] return {'kpoints': kpoints, 'path': path} def mcl(self, b, c, beta): self.name = "MCL" eta = (1 - b * cos(beta) / c) / (2 * sin(beta)**2) nu = 0.5 - eta * c * cos(beta) / b kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5, 0.0]), 'C': np.array([0.0, 0.5, 0.5]), 'D': np.array([0.5, 0.0, 0.5]), 'D_1': np.array([0.5, 0.5, -0.5]), 'E': np.array([0.5, 0.5, 0.5]), 'H': np.array([0.0, eta, 1.0 - nu]), 'H_1': np.array([0.0, 1.0 - eta, nu]), 'H_2': np.array([0.0, eta, -nu]), 'M': np.array([0.5, eta, 1.0 - nu]), 'M_1': np.array([0.5, 1 - eta, nu]), 'M_2': np.array([0.5, 1 - eta, nu]), 'X': np.array([0.0, 0.5, 0.0]), 'Y': np.array([0.0, 0.0, 0.5]), 'Y_1': np.array([0.0, 0.0, -0.5]), 'Z': np.array([0.5, 0.0, 0.0]) } path = [["\\Gamma", "Y", "H", "C", "E", "M_1", "A", "X", "H_1"], ["M", "D", "Z"], ["Y", "D"]] return {'kpoints': kpoints, 'path': path} def mclc1(self, a, b, c, alpha): self.name = "MCLC1" zeta = (2 - b * cos(alpha) / c) / (4 * sin(alpha)**2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b psi = 0.75 - a**2 / (4 * b**2 * sin(alpha)**2) phi = psi + (0.75 - psi) * b * cos(alpha) / c kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'F': np.array([1 - zeta, 1 - zeta, 1 - eta]), 'F_1': np.array([zeta, zeta, eta]), 'F_2': np.array([-zeta, -zeta, 1 - eta]), # 'F_3': np.array([1 - zeta, -zeta, 1 - eta]), 'I': np.array([phi, 1 - phi, 0.5]), 'I_1': np.array([1 - phi, phi - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'X': np.array([1 - psi, psi - 1, 0.0]), 'X_1': np.array([psi, 1 - psi, 0.0]), 'X_2': np.array([psi - 1, -psi, 0.0]), 'Y': np.array([0.5, 0.5, 0.0]), 'Y_1': np.array([-0.5, -0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "F_1"], ["Y", "X_1"], ["X", "\\Gamma", "N"], ["M", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc2(self, a, b, c, alpha): self.name = "MCLC2" zeta = (2 - b * cos(alpha) / c) / (4 * sin(alpha)**2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b psi = 0.75 - a**2 / (4 * b**2 * sin(alpha)**2) phi = psi + (0.75 - psi) * b * cos(alpha) / c kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'F': np.array([1 - zeta, 1 - zeta, 1 - eta]), 'F_1': np.array([zeta, zeta, eta]), 'F_2': np.array([-zeta, -zeta, 1 - eta]), 'F_3': np.array([1 - zeta, -zeta, 1 - eta]), 'I': np.array([phi, 1 - phi, 0.5]), 'I_1': np.array([1 - phi, phi - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'X': np.array([1 - psi, psi - 1, 0.0]), 'X_1': np.array([psi, 1 - psi, 0.0]), 'X_2': np.array([psi - 1, -psi, 0.0]), 'Y': np.array([0.5, 0.5, 0.0]), 'Y_1': np.array([-0.5, -0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "F_1"], ["N", "\\Gamma", "M"]] return {'kpoints': kpoints, 'path': path} def mclc3(self, a, b, c, alpha): self.name = "MCLC3" mu = (1 + b**2 / a**2) / 4.0 delta = b * c * cos(alpha) / (2 * a**2) zeta = mu - 0.25 + (1 - b * cos(alpha) / c) / (4 * sin(alpha)**2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b phi = 1 + zeta - 2 * mu psi = eta - 2 * delta kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([1 - phi, 1 - phi, 1 - psi]), 'F_1': np.array([phi, phi - 1, psi]), 'F_2': np.array([1 - phi, -phi, 1 - psi]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([0.5, -0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\\Gamma", "Y", "F", "H", "Z", "I", "F_1"], ["H_1", "Y_1", "X", "\\Gamma", "N"], ["M", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc4(self, a, b, c, alpha): self.name = "MCLC4" mu = (1 + b**2 / a**2) / 4.0 delta = b * c * cos(alpha) / (2 * a**2) zeta = mu - 0.25 + (1 - b * cos(alpha) / c) / (4 * sin(alpha)**2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b phi = 1 + zeta - 2 * mu psi = eta - 2 * delta kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([1 - phi, 1 - phi, 1 - psi]), 'F_1': np.array([phi, phi - 1, psi]), 'F_2': np.array([1 - phi, -phi, 1 - psi]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([0.5, -0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\\Gamma", "Y", "F", "H", "Z", "I"], ["H_1", "Y_1", "X", "\\Gamma", "N"], ["M", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc5(self, a, b, c, alpha): self.name = "MCLC5" zeta = (b**2 / a**2 + (1 - b * cos(alpha) / c) / sin(alpha)**2) / 4 eta = 0.5 + 2 * zeta * c * cos(alpha) / b mu = eta / 2 + b**2 / (4 * a**2) - b * c * cos(alpha) / (2 * a**2) nu = 2 * mu - zeta rho = 1 - zeta * a**2 / b**2 omega = (4 * nu - 1 - b**2 * sin(alpha)**2 / a**2) * c / (2 * b * cos(alpha)) delta = zeta * c * cos(alpha) / b + omega / 2 - 0.25 kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([nu, nu, omega]), 'F_1': np.array([1 - nu, 1 - nu, 1 - omega]), 'F_2': np.array([nu, nu - 1, omega]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([rho, 1 - rho, 0.5]), 'I_1': np.array([1 - rho, rho - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "H", "F_1"], ["H_1", "Y_1", "X", "\\Gamma", "N"], ["M", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def tria(self): self.name = "TRI1a" kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([0.5, 0.5, 0.0]), 'M': np.array([0.0, 0.5, 0.5]), 'N': np.array([0.5, 0.0, 0.5]), 'R': np.array([0.5, 0.5, 0.5]), 'X': np.array([0.5, 0.0, 0.0]), 'Y': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["X", "\\Gamma", "Y"], ["L", "\\Gamma", "Z"], ["N", "\\Gamma", "M"], ["R", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def trib(self): self.name = "TRI1b" kpoints = { '\\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([0.5, -0.5, 0.0]), 'M': np.array([0.0, 0.0, 0.5]), 'N': np.array([-0.5, -0.5, 0.5]), 'R': np.array([0.0, -0.5, 0.5]), 'X': np.array([0.0, -0.5, 0.0]), 'Y': np.array([0.5, 0.0, 0.0]), 'Z': np.array([-0.5, 0.0, 0.5]) } path = [["X", "\\Gamma", "Y"], ["L", "\\Gamma", "Z"], ["N", "\\Gamma", "M"], ["R", "\\Gamma"]] return {'kpoints': kpoints, 'path': path}
except (ValueError, IndexError): print("-d must be followed by an integer") exit(1) # read structure if os.path.exists(fstruct): struct = mg.Structure.from_file(fstruct) else: print("File %s does not exist" % fstruct) exit(1) # symmetry information struct_sym = SpacegroupAnalyzer(struct) print("\nLattice details:") print("----------------") print("lattice type : {0}".format(struct_sym.get_lattice_type())) print("space group : {0} ({1})".format(struct_sym.get_spacegroup_symbol(), struct_sym.get_spacegroup_number())) # Compute first brillouin zone ibz = HighSymmKpath(struct) print("ibz type : {0}".format(ibz.name)) ibz.get_kpath_plot(savefig="path.png") # print specific kpoints in the first brillouin zone print("\nList of high symmetry k-points:") print("-------------------------------") for key, val in ibz.kpath["kpoints"].items(): print("%8s %s" % (key, str(val))) # suggested path for the band structure
class HighSymmKpath(object): """ This class looks for path along high symmetry lines in the Brillouin Zone. It is based on Setyawan, W., & Curtarolo, S. (2010). High-throughput electronic band structure calculations: Challenges and tools. Computational Materials Science, 49(2), 299-312. doi:10.1016/j.commatsci.2010.05.010 It should be used with primitive structures that comply with the definition from the paper. The symmetry is determined by spglib through the SpacegroupAnalyzer class. The analyzer can be used to produce the correct primitive structure (method get_primitive_standard_structure(international_monoclinic=False)). A warning will signal possible compatibility problems with the given structure. Args: structure (Structure): Structure object symprec (float): Tolerance for symmetry finding angle_tolerance (float): Angle tolerance for symmetry finding. atol (float): Absolute tolerance used to compare the input structure with the one expected as primitive standard. A warning will be issued if the lattices don't match. """ def __init__(self, structure, symprec=0.01, angle_tolerance=5, atol=1e-8): self._structure = structure self._sym = SpacegroupAnalyzer(structure, symprec=symprec, angle_tolerance=angle_tolerance) self._prim = self._sym\ .get_primitive_standard_structure(international_monoclinic=False) self._conv = self._sym.get_conventional_standard_structure(international_monoclinic=False) self._prim_rec = self._prim.lattice.reciprocal_lattice self._kpath = None #Note: this warning will be issued for space groups 38-41, since the primitive cell must be #reformatted to match Setyawan/Curtarolo convention in order to work with the current k-path #generation scheme. if not np.allclose(self._structure.lattice.matrix, self._prim.lattice.matrix, atol=atol): warnings.warn("The input structure does not match the expected standard primitive! " "The path can be incorrect. Use at your own risk.") lattice_type = self._sym.get_lattice_type() spg_symbol = self._sym.get_space_group_symbol() if lattice_type == "cubic": if "P" in spg_symbol: self._kpath = self.cubic() elif "F" in spg_symbol: self._kpath = self.fcc() elif "I" in spg_symbol: self._kpath = self.bcc() else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "tetragonal": if "P" in spg_symbol: self._kpath = self.tet() elif "I" in spg_symbol: a = self._conv.lattice.abc[0] c = self._conv.lattice.abc[2] if c < a: self._kpath = self.bctet1(c, a) else: self._kpath = self.bctet2(c, a) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "orthorhombic": a = self._conv.lattice.abc[0] b = self._conv.lattice.abc[1] c = self._conv.lattice.abc[2] if "P" in spg_symbol: self._kpath = self.orc() elif "F" in spg_symbol: if 1 / a ** 2 > 1 / b ** 2 + 1 / c ** 2: self._kpath = self.orcf1(a, b, c) elif 1 / a ** 2 < 1 / b ** 2 + 1 / c ** 2: self._kpath = self.orcf2(a, b, c) else: self._kpath = self.orcf3(a, b, c) elif "I" in spg_symbol: self._kpath = self.orci(a, b, c) elif "C" in spg_symbol or "A" in spg_symbol: self._kpath = self.orcc(a, b, c) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "hexagonal": self._kpath = self.hex() elif lattice_type == "rhombohedral": alpha = self._prim.lattice.lengths_and_angles[1][0] if alpha < 90: self._kpath = self.rhl1(alpha * pi / 180) else: self._kpath = self.rhl2(alpha * pi / 180) elif lattice_type == "monoclinic": a, b, c = self._conv.lattice.abc alpha = self._conv.lattice.lengths_and_angles[1][0] #beta = self._conv.lattice.lengths_and_angles[1][1] if "P" in spg_symbol: self._kpath = self.mcl(b, c, alpha * pi / 180) elif "C" in spg_symbol: kgamma = self._prim_rec.lengths_and_angles[1][2] if kgamma > 90: self._kpath = self.mclc1(a, b, c, alpha * pi / 180) if kgamma == 90: self._kpath = self.mclc2(a, b, c, alpha * pi / 180) if kgamma < 90: if b * cos(alpha * pi / 180) / c\ + b ** 2 * sin(alpha * pi / 180) ** 2 / a ** 2 < 1: self._kpath = self.mclc3(a, b, c, alpha * pi / 180) if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha * pi / 180) ** 2 / a ** 2 == 1: self._kpath = self.mclc4(a, b, c, alpha * pi / 180) if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha * pi / 180) ** 2 / a ** 2 > 1: self._kpath = self.mclc5(a, b, c, alpha * pi / 180) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "triclinic": kalpha = self._prim_rec.lengths_and_angles[1][0] kbeta = self._prim_rec.lengths_and_angles[1][1] kgamma = self._prim_rec.lengths_and_angles[1][2] if kalpha > 90 and kbeta > 90 and kgamma > 90: self._kpath = self.tria() if kalpha < 90 and kbeta < 90 and kgamma < 90: self._kpath = self.trib() if kalpha > 90 and kbeta > 90 and kgamma == 90: self._kpath = self.tria() if kalpha < 90 and kbeta < 90 and kgamma == 90: self._kpath = self.trib() else: warn("Unknown lattice type %s" % lattice_type) @property def structure(self): """ Returns: The standardized primitive structure """ return self._prim @property def conventional(self): """ Returns: The conventional cell structure """ return self._conv @property def prim(self): """ Returns: The primitive cell structure """ return self._prim @property def prim_rec(self): """ Returns: The primitive reciprocal cell structure """ return self._prim_rec @property def kpath(self): """ Returns: The symmetry line path in reciprocal space """ return self._kpath def get_kpoints(self, line_density=20, coords_are_cartesian=True): """ Returns: the kpoints along the paths in cartesian coordinates together with the labels for symmetry points -Wei """ list_k_points = [] sym_point_labels = [] for b in self.kpath['path']: for i in range(1, len(b)): start = np.array(self.kpath['kpoints'][b[i - 1]]) end = np.array(self.kpath['kpoints'][b[i]]) distance = np.linalg.norm( self._prim_rec.get_cartesian_coords(start) - self._prim_rec.get_cartesian_coords(end)) nb = int(ceil(distance * line_density)) sym_point_labels.extend([b[i - 1]] + [''] * (nb - 1) + [b[i]]) list_k_points.extend( [self._prim_rec.get_cartesian_coords(start) + float(i) / float(nb) * (self._prim_rec.get_cartesian_coords(end) - self._prim_rec.get_cartesian_coords(start)) for i in range(0, nb + 1)]) if coords_are_cartesian: return list_k_points, sym_point_labels else: frac_k_points = [self._prim_rec.get_fractional_coords(k) for k in list_k_points] return frac_k_points, sym_point_labels def cubic(self): self.name = "CUB" kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'X': np.array([0.0, 0.5, 0.0]), 'R': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.5, 0.0])} path = [["\\Gamma", "X", "M", "\\Gamma", "R", "X"], ["M", "R"]] return {'kpoints': kpoints, 'path': path} def fcc(self): self.name = "FCC" kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'K': np.array([3.0 / 8.0, 3.0 / 8.0, 3.0 / 4.0]), 'L': np.array([0.5, 0.5, 0.5]), 'U': np.array([5.0 / 8.0, 1.0 / 4.0, 5.0 / 8.0]), 'W': np.array([0.5, 1.0 / 4.0, 3.0 / 4.0]), 'X': np.array([0.5, 0.0, 0.5])} path = [["\\Gamma", "X", "W", "K", "\\Gamma", "L", "U", "W", "L", "K"], ["U", "X"]] return {'kpoints': kpoints, 'path': path} def bcc(self): self.name = "BCC" kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'H': np.array([0.5, -0.5, 0.5]), 'P': np.array([0.25, 0.25, 0.25]), 'N': np.array([0.0, 0.0, 0.5])} path = [["\\Gamma", "H", "N", "\\Gamma", "P", "H"], ["P", "N"]] return {'kpoints': kpoints, 'path': path} def tet(self): self.name = "TET" kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.5, 0.0]), 'R': np.array([0.0, 0.5, 0.5]), 'X': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\\Gamma", "X", "M", "\\Gamma", "Z", "R", "A", "Z"], ["X", "R"], ["M", "A"]] return {'kpoints': kpoints, 'path': path} def bctet1(self, c, a): self.name = "BCT1" eta = (1 + c ** 2 / a ** 2) / 4.0 kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'M': np.array([-0.5, 0.5, 0.5]), 'N': np.array([0.0, 0.5, 0.0]), 'P': np.array([0.25, 0.25, 0.25]), 'X': np.array([0.0, 0.0, 0.5]), 'Z': np.array([eta, eta, -eta]), 'Z_1': np.array([-eta, 1 - eta, eta])} path = [["\\Gamma", "X", "M", "\\Gamma", "Z", "P", "N", "Z_1", "M"], ["X", "P"]] return {'kpoints': kpoints, 'path': path} def bctet2(self, c, a): self.name = "BCT2" eta = (1 + a ** 2 / c ** 2) / 4.0 zeta = a ** 2 / (2 * c ** 2) kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.0, 0.5, 0.0]), 'P': np.array([0.25, 0.25, 0.25]), '\\Sigma': np.array([-eta, eta, eta]), '\\Sigma_1': np.array([eta, 1 - eta, -eta]), 'X': np.array([0.0, 0.0, 0.5]), 'Y': np.array([-zeta, zeta, 0.5]), 'Y_1': np.array([0.5, 0.5, -zeta]), 'Z': np.array([0.5, 0.5, -0.5])} path = [["\\Gamma", "X", "Y", "\\Sigma", "\\Gamma", "Z", "\\Sigma_1", "N", "P", "Y_1", "Z"], ["X", "P"]] return {'kpoints': kpoints, 'path': path} def orc(self): self.name = "ORC" kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'R': np.array([0.5, 0.5, 0.5]), 'S': np.array([0.5, 0.5, 0.0]), 'T': np.array([0.0, 0.5, 0.5]), 'U': np.array([0.5, 0.0, 0.5]), 'X': np.array([0.5, 0.0, 0.0]), 'Y': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\\Gamma", "X", "S", "Y", "\\Gamma", "Z", "U", "R", "T", "Z"], ["Y", "T"], ["U", "X"], ["S", "R"]] return {'kpoints': kpoints, 'path': path} def orcf1(self, a, b, c): self.name = "ORCF1" zeta = (1 + a ** 2 / b ** 2 - a ** 2 / c ** 2) / 4 eta = (1 + a ** 2 / b ** 2 + a ** 2 / c ** 2) / 4 kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5 + zeta, zeta]), 'A_1': np.array([0.5, 0.5 - zeta, 1 - zeta]), 'L': np.array([0.5, 0.5, 0.5]), 'T': np.array([1, 0.5, 0.5]), 'X': np.array([0.0, eta, eta]), 'X_1': np.array([1, 1 - eta, 1 - eta]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0])} path = [["\\Gamma", "Y", "T", "Z", "\\Gamma", "X", "A_1", "Y"], ["T", "X_1"], ["X", "A", "Z"], ["L", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def orcf2(self, a, b, c): self.name = "ORCF2" phi = (1 + c ** 2 / b ** 2 - c ** 2 / a ** 2) / 4 eta = (1 + a ** 2 / b ** 2 - a ** 2 / c ** 2) / 4 delta = (1 + b ** 2 / a ** 2 - b ** 2 / c ** 2) / 4 kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'C': np.array([0.5, 0.5 - eta, 1 - eta]), 'C_1': np.array([0.5, 0.5 + eta, eta]), 'D': np.array([0.5 - delta, 0.5, 1 - delta]), 'D_1': np.array([0.5 + delta, 0.5, delta]), 'L': np.array([0.5, 0.5, 0.5]), 'H': np.array([1 - phi, 0.5 - phi, 0.5]), 'H_1': np.array([phi, 0.5 + phi, 0.5]), 'X': np.array([0.0, 0.5, 0.5]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0])} path = [["\\Gamma", "Y", "C", "D", "X", "\\Gamma", "Z", "D_1", "H", "C"], ["C_1", "Z"], ["X", "H_1"], ["H", "Y"], ["L", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def orcf3(self, a, b, c): self.name = "ORCF3" zeta = (1 + a ** 2 / b ** 2 - a ** 2 / c ** 2) / 4 eta = (1 + a ** 2 / b ** 2 + a ** 2 / c ** 2) / 4 kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5 + zeta, zeta]), 'A_1': np.array([0.5, 0.5 - zeta, 1 - zeta]), 'L': np.array([0.5, 0.5, 0.5]), 'T': np.array([1, 0.5, 0.5]), 'X': np.array([0.0, eta, eta]), 'X_1': np.array([1, 1 - eta, 1 - eta]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0])} path = [["\\Gamma", "Y", "T", "Z", "\\Gamma", "X", "A_1", "Y"], ["X", "A", "Z"], ["L", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def orci(self, a, b, c): self.name = "ORCI" zeta = (1 + a ** 2 / c ** 2) / 4 eta = (1 + b ** 2 / c ** 2) / 4 delta = (b ** 2 - a ** 2) / (4 * c ** 2) mu = (a ** 2 + b ** 2) / (4 * c ** 2) kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([-mu, mu, 0.5 - delta]), 'L_1': np.array([mu, -mu, 0.5 + delta]), 'L_2': np.array([0.5 - delta, 0.5 + delta, -mu]), 'R': np.array([0.0, 0.5, 0.0]), 'S': np.array([0.5, 0.0, 0.0]), 'T': np.array([0.0, 0.0, 0.5]), 'W': np.array([0.25, 0.25, 0.25]), 'X': np.array([-zeta, zeta, zeta]), 'X_1': np.array([zeta, 1 - zeta, -zeta]), 'Y': np.array([eta, -eta, eta]), 'Y_1': np.array([1 - eta, eta, -eta]), 'Z': np.array([0.5, 0.5, -0.5])} path = [["\\Gamma", "X", "L", "T", "W", "R", "X_1", "Z", "\\Gamma", "Y", "S", "W"], ["L_1", "Y"], ["Y_1", "Z"]] return {'kpoints': kpoints, 'path': path} def orcc(self, a, b, c): self.name = "ORCC" zeta = (1 + a ** 2 / b ** 2) / 4 kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([zeta, zeta, 0.5]), 'A_1': np.array([-zeta, 1 - zeta, 0.5]), 'R': np.array([0.0, 0.5, 0.5]), 'S': np.array([0.0, 0.5, 0.0]), 'T': np.array([-0.5, 0.5, 0.5]), 'X': np.array([zeta, zeta, 0.0]), 'X_1': np.array([-zeta, 1 - zeta, 0.0]), 'Y': np.array([-0.5, 0.5, 0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\\Gamma", "X", "S", "R", "A", "Z", "\\Gamma", "Y", "X_1", "A_1", "T", "Y"], ["Z", "T"]] return {'kpoints': kpoints, 'path': path} def hex(self): self.name = "HEX" kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.0, 0.0, 0.5]), 'H': np.array([1.0 / 3.0, 1.0 / 3.0, 0.5]), 'K': np.array([1.0 / 3.0, 1.0 / 3.0, 0.0]), 'L': np.array([0.5, 0.0, 0.5]), 'M': np.array([0.5, 0.0, 0.0])} path = [["\\Gamma", "M", "K", "\\Gamma", "A", "L", "H", "A"], ["L", "M"], ["K", "H"]] return {'kpoints': kpoints, 'path': path} def rhl1(self, alpha): self.name = "RHL1" eta = (1 + 4 * cos(alpha)) / (2 + 4 * cos(alpha)) nu = 3.0 / 4.0 - eta / 2.0 kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'B': np.array([eta, 0.5, 1.0 - eta]), 'B_1': np.array([1.0 / 2.0, 1.0 - eta, eta - 1.0]), 'F': np.array([0.5, 0.5, 0.0]), 'L': np.array([0.5, 0.0, 0.0]), 'L_1': np.array([0.0, 0.0, -0.5]), 'P': np.array([eta, nu, nu]), 'P_1': np.array([1.0 - nu, 1.0 - nu, 1.0 - eta]), 'P_2': np.array([nu, nu, eta - 1.0]), 'Q': np.array([1.0 - nu, nu, 0.0]), 'X': np.array([nu, 0.0, -nu]), 'Z': np.array([0.5, 0.5, 0.5])} path = [["\\Gamma", "L", "B_1"], ["B", "Z", "\\Gamma", "X"], ["Q", "F", "P_1", "Z"], ["L", "P"]] return {'kpoints': kpoints, 'path': path} def rhl2(self, alpha): self.name = "RHL2" eta = 1 / (2 * tan(alpha / 2.0) ** 2) nu = 3.0 / 4.0 - eta / 2.0 kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([0.5, -0.5, 0.0]), 'L': np.array([0.5, 0.0, 0.0]), 'P': np.array([1 - nu, -nu, 1 - nu]), 'P_1': np.array([nu, nu - 1.0, nu - 1.0]), 'Q': np.array([eta, eta, eta]), 'Q_1': np.array([1.0 - eta, -eta, -eta]), 'Z': np.array([0.5, -0.5, 0.5])} path = [["\\Gamma", "P", "Z", "Q", "\\Gamma", "F", "P_1", "Q_1", "L", "Z"]] return {'kpoints': kpoints, 'path': path} def mcl(self, b, c, beta): self.name = "MCL" eta = (1 - b * cos(beta) / c) / (2 * sin(beta) ** 2) nu = 0.5 - eta * c * cos(beta) / b kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5, 0.0]), 'C': np.array([0.0, 0.5, 0.5]), 'D': np.array([0.5, 0.0, 0.5]), 'D_1': np.array([0.5, 0.5, -0.5]), 'E': np.array([0.5, 0.5, 0.5]), 'H': np.array([0.0, eta, 1.0 - nu]), 'H_1': np.array([0.0, 1.0 - eta, nu]), 'H_2': np.array([0.0, eta, -nu]), 'M': np.array([0.5, eta, 1.0 - nu]), 'M_1': np.array([0.5, 1 - eta, nu]), 'M_2': np.array([0.5, 1 - eta, nu]), 'X': np.array([0.0, 0.5, 0.0]), 'Y': np.array([0.0, 0.0, 0.5]), 'Y_1': np.array([0.0, 0.0, -0.5]), 'Z': np.array([0.5, 0.0, 0.0])} path = [["\\Gamma", "Y", "H", "C", "E", "M_1", "A", "X", "H_1"], ["M", "D", "Z"], ["Y", "D"]] return {'kpoints': kpoints, 'path': path} def mclc1(self, a, b, c, alpha): self.name = "MCLC1" zeta = (2 - b * cos(alpha) / c) / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b psi = 0.75 - a ** 2 / (4 * b ** 2 * sin(alpha) ** 2) phi = psi + (0.75 - psi) * b * cos(alpha) / c kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'F': np.array([1 - zeta, 1 - zeta, 1 - eta]), 'F_1': np.array([zeta, zeta, eta]), 'F_2': np.array([-zeta, -zeta, 1 - eta]), #'F_3': np.array([1 - zeta, -zeta, 1 - eta]), 'I': np.array([phi, 1 - phi, 0.5]), 'I_1': np.array([1 - phi, phi - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'X': np.array([1 - psi, psi - 1, 0.0]), 'X_1': np.array([psi, 1 - psi, 0.0]), 'X_2': np.array([psi - 1, -psi, 0.0]), 'Y': np.array([0.5, 0.5, 0.0]), 'Y_1': np.array([-0.5, -0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "F_1"], ["Y", "X_1"], ["X", "\\Gamma", "N"], ["M", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc2(self, a, b, c, alpha): self.name = "MCLC2" zeta = (2 - b * cos(alpha) / c) / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b psi = 0.75 - a ** 2 / (4 * b ** 2 * sin(alpha) ** 2) phi = psi + (0.75 - psi) * b * cos(alpha) / c kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'F': np.array([1 - zeta, 1 - zeta, 1 - eta]), 'F_1': np.array([zeta, zeta, eta]), 'F_2': np.array([-zeta, -zeta, 1 - eta]), 'F_3': np.array([1 - zeta, -zeta, 1 - eta]), 'I': np.array([phi, 1 - phi, 0.5]), 'I_1': np.array([1 - phi, phi - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'X': np.array([1 - psi, psi - 1, 0.0]), 'X_1': np.array([psi, 1 - psi, 0.0]), 'X_2': np.array([psi - 1, -psi, 0.0]), 'Y': np.array([0.5, 0.5, 0.0]), 'Y_1': np.array([-0.5, -0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "F_1"], ["N", "\\Gamma", "M"]] return {'kpoints': kpoints, 'path': path} def mclc3(self, a, b, c, alpha): self.name = "MCLC3" mu = (1 + b ** 2 / a ** 2) / 4.0 delta = b * c * cos(alpha) / (2 * a ** 2) zeta = mu - 0.25 + (1 - b * cos(alpha) / c)\ / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b phi = 1 + zeta - 2 * mu psi = eta - 2 * delta kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([1 - phi, 1 - phi, 1 - psi]), 'F_1': np.array([phi, phi - 1, psi]), 'F_2': np.array([1 - phi, -phi, 1 - psi]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([0.5, -0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\\Gamma", "Y", "F", "H", "Z", "I", "F_1"], ["H_1", "Y_1", "X", "\\Gamma", "N"], ["M", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc4(self, a, b, c, alpha): self.name = "MCLC4" mu = (1 + b ** 2 / a ** 2) / 4.0 delta = b * c * cos(alpha) / (2 * a ** 2) zeta = mu - 0.25 + (1 - b * cos(alpha) / c)\ / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b phi = 1 + zeta - 2 * mu psi = eta - 2 * delta kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([1 - phi, 1 - phi, 1 - psi]), 'F_1': np.array([phi, phi - 1, psi]), 'F_2': np.array([1 - phi, -phi, 1 - psi]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([0.5, -0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\\Gamma", "Y", "F", "H", "Z", "I"], ["H_1", "Y_1", "X", "\\Gamma", "N"], ["M", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc5(self, a, b, c, alpha): self.name = "MCLC5" zeta = (b ** 2 / a ** 2 + (1 - b * cos(alpha) / c) / sin(alpha) ** 2) / 4 eta = 0.5 + 2 * zeta * c * cos(alpha) / b mu = eta / 2 + b ** 2 / (4 * a ** 2) \ - b * c * cos(alpha) / (2 * a ** 2) nu = 2 * mu - zeta rho = 1 - zeta * a ** 2 / b ** 2 omega = (4 * nu - 1 - b ** 2 * sin(alpha) ** 2 / a ** 2)\ * c / (2 * b * cos(alpha)) delta = zeta * c * cos(alpha) / b + omega / 2 - 0.25 kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([nu, nu, omega]), 'F_1': np.array([1 - nu, 1 - nu, 1 - omega]), 'F_2': np.array([nu, nu - 1, omega]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([rho, 1 - rho, 0.5]), 'I_1': np.array([1 - rho, rho - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "H", "F_1"], ["H_1", "Y_1", "X", "\\Gamma", "N"], ["M", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def tria(self): self.name = "TRI1a" kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([0.5, 0.5, 0.0]), 'M': np.array([0.0, 0.5, 0.5]), 'N': np.array([0.5, 0.0, 0.5]), 'R': np.array([0.5, 0.5, 0.5]), 'X': np.array([0.5, 0.0, 0.0]), 'Y': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["X", "\\Gamma", "Y"], ["L", "\\Gamma", "Z"], ["N", "\\Gamma", "M"], ["R", "\\Gamma"]] return {'kpoints': kpoints, 'path': path} def trib(self): self.name = "TRI1b" kpoints = {'\\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([0.5, -0.5, 0.0]), 'M': np.array([0.0, 0.0, 0.5]), 'N': np.array([-0.5, -0.5, 0.5]), 'R': np.array([0.0, -0.5, 0.5]), 'X': np.array([0.0, -0.5, 0.0]), 'Y': np.array([0.5, 0.0, 0.0]), 'Z': np.array([-0.5, 0.0, 0.5])} path = [["X", "\\Gamma", "Y"], ["L", "\\Gamma", "Z"], ["N", "\\Gamma", "M"], ["R", "\\Gamma"]] return {'kpoints': kpoints, 'path': path}
class HighSymmKpath(object): """ This class looks for path along high symmetry lines in the Brillouin Zone. It is based on Setyawan, W., & Curtarolo, S. (2010). High-throughput electronic band structure calculations: Challenges and tools. Computational Materials Science, 49(2), 299-312. doi:10.1016/j.commatsci.2010.05.010 The symmetry is determined by spglib through the SpacegroupAnalyzer class Args: structure (Structure): Structure object symprec (float): Tolerance for symmetry finding angle_tolerance (float): Angle tolerance for symmetry finding. """ def __init__(self, structure, symprec=0.01, angle_tolerance=5): self._structure = structure self._sym = SpacegroupAnalyzer(structure, symprec=symprec, angle_tolerance=angle_tolerance) self._prim = self._sym\ .get_primitive_standard_structure(international_monoclinic=False) self._conv = self._sym.get_conventional_standard_structure( international_monoclinic=False) self._prim_rec = self._prim.lattice.reciprocal_lattice self._kpath = None lattice_type = self._sym.get_lattice_type() spg_symbol = self._sym.get_spacegroup_symbol() if lattice_type == "cubic": if "P" in spg_symbol: self._kpath = self.cubic() elif "F" in spg_symbol: self._kpath = self.fcc() elif "I" in spg_symbol: self._kpath = self.bcc() else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "tetragonal": if "P" in spg_symbol: self._kpath = self.tet() elif "I" in spg_symbol: a = self._conv.lattice.abc[0] c = self._conv.lattice.abc[2] if c < a: self._kpath = self.bctet1(c, a) else: self._kpath = self.bctet2(c, a) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "orthorhombic": a = self._conv.lattice.abc[0] b = self._conv.lattice.abc[1] c = self._conv.lattice.abc[2] if "P" in spg_symbol: self._kpath = self.orc() elif "F" in spg_symbol: if 1 / a**2 > 1 / b**2 + 1 / c**2: self._kpath = self.orcf1(a, b, c) elif 1 / a**2 < 1 / b**2 + 1 / c**2: self._kpath = self.orcf2(a, b, c) else: self._kpath = self.orcf3(a, b, c) elif "I" in spg_symbol: self._kpath = self.orci(a, b, c) elif "C" in spg_symbol: self._kpath = self.orcc(a, b, c) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "hexagonal": self._kpath = self.hex() elif lattice_type == "rhombohedral": alpha = self._prim.lattice.lengths_and_angles[1][0] if alpha < 90: self._kpath = self.rhl1(alpha * pi / 180) else: self._kpath = self.rhl2(alpha * pi / 180) elif lattice_type == "monoclinic": a, b, c = self._conv.lattice.abc alpha = self._conv.lattice.lengths_and_angles[1][0] #beta = self._conv.lattice.lengths_and_angles[1][1] if "P" in spg_symbol: self._kpath = self.mcl(b, c, alpha * pi / 180) elif "C" in spg_symbol: kgamma = self._prim_rec.lengths_and_angles[1][2] if kgamma > 90: self._kpath = self.mclc1(a, b, c, alpha * pi / 180) if kgamma == 90: self._kpath = self.mclc2(a, b, c, alpha * pi / 180) if kgamma < 90: if b * cos(alpha * pi / 180) / c\ + b ** 2 * sin(alpha) ** 2 / a ** 2 < 1: self._kpath = self.mclc3(a, b, c, alpha * pi / 180) if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha) ** 2 / a ** 2 == 1: self._kpath = self.mclc4(a, b, c, alpha * pi / 180) if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha) ** 2 / a ** 2 > 1: self._kpath = self.mclc5(a, b, c, alpha * pi / 180) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "triclinic": kalpha = self._prim_rec.lengths_and_angles[1][0] kbeta = self._prim_rec.lengths_and_angles[1][1] kgamma = self._prim_rec.lengths_and_angles[1][2] if kalpha > 90 and kbeta > 90 and kgamma > 90: self._kpath = self.tria() if kalpha < 90 and kbeta < 90 and kgamma < 90: self._kpath = self.trib() if kalpha > 90 and kbeta > 90 and kgamma == 90: self._kpath = self.tria() if kalpha < 90 and kbeta < 90 and kgamma == 90: self._kpath = self.trib() else: warn("Unknown lattice type %s" % lattice_type) @property def structure(self): """ Returns: The standardized primitive structure """ return self._prim @property def kpath(self): """ Returns: The symmetry line path in reciprocal space """ return self._kpath def get_kpoints(self, line_density=20, coords_are_cartesian=True): """ Returns: the kpoints along the paths in cartesian coordinates together with the labels for symmetry points -Wei """ list_k_points = [] sym_point_labels = [] for b in self.kpath['path']: for i in range(1, len(b)): start = np.array(self.kpath['kpoints'][b[i - 1]]) end = np.array(self.kpath['kpoints'][b[i]]) distance = np.linalg.norm( self._prim_rec.get_cartesian_coords(start) - self._prim_rec.get_cartesian_coords(end)) nb = int(ceil(distance * line_density)) sym_point_labels.extend([b[i - 1]] + [''] * (nb - 1) + [b[i]]) list_k_points.extend([ self._prim_rec.get_cartesian_coords(start) + float(i) / float(nb) * (self._prim_rec.get_cartesian_coords(end) - self._prim_rec.get_cartesian_coords(start)) for i in range(0, nb + 1) ]) if coords_are_cartesian: return list_k_points, sym_point_labels else: frac_k_points = [ self._prim_rec.get_fractional_coords(k) for k in list_k_points ] return frac_k_points, sym_point_labels def get_kpath_plot(self, **kwargs): """ Gives the plot (as a matplotlib object) of the symmetry line path in the Brillouin Zone. Returns: `matplotlib` figure. ================ ============================================================== kwargs Meaning ================ ============================================================== show True to show the figure (Default). savefig 'abc.png' or 'abc.eps'* to save the figure to a file. ================ ============================================================== """ import itertools import matplotlib.pyplot as plt from mpl_toolkits.mplot3d import axes3d def _plot_shape_skeleton(bz, style): for iface in range(len(bz)): for line in itertools.combinations(bz[iface], 2): for jface in range(len(bz)): if iface < jface and line[0] in bz[jface]\ and line[1] in bz[jface]: ax.plot([line[0][0], line[1][0]], [line[0][1], line[1][1]], [line[0][2], line[1][2]], style) def _plot_lattice(lattice): vertex1 = lattice.get_cartesian_coords([0.0, 0.0, 0.0]) vertex2 = lattice.get_cartesian_coords([1.0, 0.0, 0.0]) ax.plot([vertex1[0], vertex2[0]], [vertex1[1], vertex2[1]], [vertex1[2], vertex2[2]], color='g', linewidth=3) vertex2 = lattice.get_cartesian_coords([0.0, 1.0, 0.0]) ax.plot([vertex1[0], vertex2[0]], [vertex1[1], vertex2[1]], [vertex1[2], vertex2[2]], color='g', linewidth=3) vertex2 = lattice.get_cartesian_coords([0.0, 0.0, 1.0]) ax.plot([vertex1[0], vertex2[0]], [vertex1[1], vertex2[1]], [vertex1[2], vertex2[2]], color='g', linewidth=3) def _plot_kpath(kpath, lattice): for line in kpath['path']: for k in range(len(line) - 1): vertex1 = lattice.get_cartesian_coords( kpath['kpoints'][line[k]]) vertex2 = lattice.get_cartesian_coords( kpath['kpoints'][line[k + 1]]) ax.plot([vertex1[0], vertex2[0]], [vertex1[1], vertex2[1]], [vertex1[2], vertex2[2]], color='r', linewidth=3) def _plot_labels(kpath, lattice): for k in kpath['kpoints']: label = k if k.startswith("\\") or k.find("_") != -1: label = "$" + k + "$" off = 0.01 ax.text( lattice.get_cartesian_coords(kpath['kpoints'][k])[0] + off, lattice.get_cartesian_coords(kpath['kpoints'][k])[1] + off, lattice.get_cartesian_coords(kpath['kpoints'][k])[2] + off, label, color='b', size='25') ax.scatter( [lattice.get_cartesian_coords(kpath['kpoints'][k])[0]], [lattice.get_cartesian_coords(kpath['kpoints'][k])[1]], [lattice.get_cartesian_coords(kpath['kpoints'][k])[2]], color='b') fig = plt.figure() ax = axes3d.Axes3D(fig) _plot_lattice(self._prim_rec) _plot_shape_skeleton(self._prim_rec.get_wigner_seitz_cell(), '-k') _plot_kpath(self.kpath, self._prim_rec) _plot_labels(self.kpath, self._prim_rec) ax.axis("off") show = kwargs.pop("show", True) if show: plt.show() savefig = kwargs.pop("savefig", None) if savefig: fig.savefig(savefig) return fig def cubic(self): self.name = "CUB" kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'X': np.array([0.0, 0.5, 0.0]), 'R': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.5, 0.0]) } path = [["\Gamma", "X", "M", "\Gamma", "R", "X"], ["M", "R"]] return {'kpoints': kpoints, 'path': path} def fcc(self): self.name = "FCC" kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'K': np.array([3.0 / 8.0, 3.0 / 8.0, 3.0 / 4.0]), 'L': np.array([0.5, 0.5, 0.5]), 'U': np.array([5.0 / 8.0, 1.0 / 4.0, 5.0 / 8.0]), 'W': np.array([0.5, 1.0 / 4.0, 3.0 / 4.0]), 'X': np.array([0.5, 0.0, 0.5]) } path = [["\Gamma", "X", "W", "K", "\Gamma", "L", "U", "W", "L", "K"], ["U", "X"]] return {'kpoints': kpoints, 'path': path} def bcc(self): self.name = "BCC" kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'H': np.array([0.5, -0.5, 0.5]), 'P': np.array([0.25, 0.25, 0.25]), 'N': np.array([0.0, 0.0, 0.5]) } path = [["\Gamma", "H", "N", "\Gamma", "P", "H"], ["P", "N"]] return {'kpoints': kpoints, 'path': path} def tet(self): self.name = "TET" kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.5, 0.0]), 'R': np.array([0.0, 0.5, 0.5]), 'X': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\Gamma", "X", "M", "\Gamma", "Z", "R", "A", "Z"], ["X", "R"], ["M", "A"]] return {'kpoints': kpoints, 'path': path} def bctet1(self, c, a): self.name = "BCT1" eta = (1 + c**2 / a**2) / 4.0 kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'M': np.array([-0.5, 0.5, 0.5]), 'N': np.array([0.0, 0.5, 0.0]), 'P': np.array([0.25, 0.25, 0.25]), 'X': np.array([0.0, 0.0, 0.5]), 'Z': np.array([eta, eta, -eta]), 'Z_1': np.array([-eta, 1 - eta, eta]) } path = [["\Gamma", "X", "M", "\Gamma", "Z", "P", "N", "Z_1", "M"], ["X", "P"]] return {'kpoints': kpoints, 'path': path} def bctet2(self, c, a): self.name = "BCT2" eta = (1 + a**2 / c**2) / 4.0 zeta = a**2 / (2 * c**2) kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.0, 0.5, 0.0]), 'P': np.array([0.25, 0.25, 0.25]), '\Sigma': np.array([-eta, eta, eta]), '\Sigma_1': np.array([eta, 1 - eta, -eta]), 'X': np.array([0.0, 0.0, 0.5]), 'Y': np.array([-zeta, zeta, 0.5]), 'Y_1': np.array([0.5, 0.5, -zeta]), 'Z': np.array([0.5, 0.5, -0.5]) } path = [[ "\Gamma", "X", "Y", "\Sigma", "\Gamma", "Z", "\Sigma_1", "N", "P", "Y_1", "Z" ], ["X", "P"]] return {'kpoints': kpoints, 'path': path} def orc(self): self.name = "ORC" kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'R': np.array([0.5, 0.5, 0.5]), 'S': np.array([0.5, 0.5, 0.0]), 'T': np.array([0.0, 0.5, 0.5]), 'U': np.array([0.5, 0.0, 0.5]), 'X': np.array([0.5, 0.0, 0.0]), 'Y': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\Gamma", "X", "S", "Y", "\Gamma", "Z", "U", "R", "T", "Z"], ["Y", "T"], ["U", "X"], ["S", "R"]] return {'kpoints': kpoints, 'path': path} def orcf1(self, a, b, c): self.name = "ORCF1" zeta = (1 + a**2 / b**2 - a**2 / c**2) / 4 eta = (1 + a**2 / b**2 + a**2 / c**2) / 4 kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5 + zeta, zeta]), 'A_1': np.array([0.5, 0.5 - zeta, 1 - zeta]), 'L': np.array([0.5, 0.5, 0.5]), 'T': np.array([1, 0.5, 0.5]), 'X': np.array([0.0, eta, eta]), 'X_1': np.array([1, 1 - eta, 1 - eta]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0]) } path = [["\Gamma", "Y", "T", "Z", "\Gamma", "X", "A_1", "Y"], ["T", "X_1"], ["X", "A", "Z"], ["L", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def orcf2(self, a, b, c): self.name = "ORCF2" phi = (1 + c**2 / b**2 - c**2 / a**2) / 4 eta = (1 + a**2 / b**2 - a**2 / c**2) / 4 delta = (1 + b**2 / a**2 - b**2 / c**2) / 4 kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'C': np.array([0.5, 0.5 - eta, 1 - eta]), 'C_1': np.array([0.5, 0.5 + eta, eta]), 'D': np.array([0.5 - delta, 0.5, 1 - delta]), 'D_1': np.array([0.5 + delta, 0.5, delta]), 'L': np.array([0.5, 0.5, 0.5]), 'H': np.array([1 - phi, 0.5 - phi, 0.5]), 'H_1': np.array([phi, 0.5 + phi, 0.5]), 'X': np.array([0.0, 0.5, 0.5]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0]) } path = [["\Gamma", "Y", "C", "D", "X", "\Gamma", "Z", "D_1", "H", "C"], ["C_1", "Z"], ["X", "H_1"], ["H", "Y"], ["L", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def orcf3(self, a, b, c): self.name = "ORCF3" zeta = (1 + a**2 / b**2 - a**2 / c**2) / 4 eta = (1 + a**2 / b**2 + a**2 / c**2) / 4 kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5 + zeta, zeta]), 'A_1': np.array([0.5, 0.5 - zeta, 1 - zeta]), 'L': np.array([0.5, 0.5, 0.5]), 'T': np.array([1, 0.5, 0.5]), 'X': np.array([0.0, eta, eta]), 'X_1': np.array([1, 1 - eta, 1 - eta]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0]) } path = [["\Gamma", "Y", "T", "Z", "\Gamma", "X", "A_1", "Y"], ["X", "A", "Z"], ["L", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def orci(self, a, b, c): self.name = "ORCI" zeta = (1 + a**2 / c**2) / 4 eta = (1 + b**2 / c**2) / 4 delta = (b**2 - a**2) / (4 * c**2) mu = (a**2 + b**2) / (4 * c**2) kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([-mu, mu, 0.5 - delta]), 'L_1': np.array([mu, -mu, 0.5 + delta]), 'L_2': np.array([0.5 - delta, 0.5 + delta, -mu]), 'R': np.array([0.0, 0.5, 0.0]), 'S': np.array([0.5, 0.0, 0.0]), 'T': np.array([0.0, 0.0, 0.5]), 'W': np.array([0.25, 0.25, 0.25]), 'X': np.array([-zeta, zeta, zeta]), 'X_1': np.array([zeta, 1 - zeta, -zeta]), 'Y': np.array([eta, -eta, eta]), 'Y_1': np.array([1 - eta, eta, -eta]), 'Z': np.array([0.5, 0.5, -0.5]) } path = [[ "\Gamma", "X", "L", "T", "W", "R", "X_1", "Z", "\Gamma", "Y", "S", "W" ], ["L_1", "Y"], ["Y_1", "Z"]] return {'kpoints': kpoints, 'path': path} def orcc(self, a, b, c): self.name = "ORCC" zeta = (1 + a**2 / b**2) / 4 kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([zeta, zeta, 0.5]), 'A_1': np.array([-zeta, 1 - zeta, 0.5]), 'R': np.array([0.0, 0.5, 0.5]), 'S': np.array([0.0, 0.5, 0.0]), 'T': np.array([-0.5, 0.5, 0.5]), 'X': np.array([zeta, zeta, 0.0]), 'X_1': np.array([-zeta, 1 - zeta, 0.0]), 'Y': np.array([-0.5, 0.5, 0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [[ "\Gamma", "X", "S", "R", "A", "Z", "\Gamma", "Y", "X_1", "A_1", "T", "Y" ], ["Z", "T"]] return {'kpoints': kpoints, 'path': path} def hex(self): self.name = "HEX" kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.0, 0.0, 0.5]), 'H': np.array([1.0 / 3.0, 1.0 / 3.0, 0.5]), 'K': np.array([1.0 / 3.0, 1.0 / 3.0, 0.0]), 'L': np.array([0.5, 0.0, 0.5]), 'M': np.array([0.5, 0.0, 0.0]) } path = [["\Gamma", "M", "K", "\Gamma", "A", "L", "H", "A"], ["L", "M"], ["K", "H"]] return {'kpoints': kpoints, 'path': path} def rhl1(self, alpha): self.name = "RHL1" eta = (1 + 4 * cos(alpha)) / (2 + 4 * cos(alpha)) nu = 3.0 / 4.0 - eta / 2.0 kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'B': np.array([eta, 0.5, 1.0 - eta]), 'B_1': np.array([1.0 / 2.0, 1.0 - eta, eta - 1.0]), 'F': np.array([0.5, 0.5, 0.0]), 'L': np.array([0.5, 0.0, 0.0]), 'L_1': np.array([0.0, 0.0, -0.5]), 'P': np.array([eta, nu, nu]), 'P_1': np.array([1.0 - nu, 1.0 - nu, 1.0 - eta]), 'P_2': np.array([nu, nu, eta - 1.0]), 'Q': np.array([1.0 - nu, nu, 0.0]), 'X': np.array([nu, 0.0, -nu]), 'Z': np.array([0.5, 0.5, 0.5]) } path = [["\Gamma", "L", "B_1"], ["B", "Z", "\Gamma", "X"], ["Q", "F", "P_1", "Z"], ["L", "P"]] return {'kpoints': kpoints, 'path': path} def rhl2(self, alpha): self.name = "RHL2" eta = 1 / (2 * tan(alpha / 2.0)**2) nu = 3.0 / 4.0 - eta / 2.0 kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([0.5, -0.5, 0.0]), 'L': np.array([0.5, 0.0, 0.0]), 'P': np.array([1 - nu, -nu, 1 - nu]), 'P_1': np.array([nu, nu - 1.0, nu - 1.0]), 'Q': np.array([eta, eta, eta]), 'Q_1': np.array([1.0 - eta, -eta, -eta]), 'Z': np.array([0.5, -0.5, 0.5]) } path = [[ "\Gamma", "P", "Z", "Q", "\Gamma", "F", "P_1", "Q_1", "L", "Z" ]] return {'kpoints': kpoints, 'path': path} def mcl(self, b, c, beta): self.name = "MCL" eta = (1 - b * cos(beta) / c) / (2 * sin(beta)**2) nu = 0.5 - eta * c * cos(beta) / b kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5, 0.0]), 'C': np.array([0.0, 0.5, 0.5]), 'D': np.array([0.5, 0.0, 0.5]), 'D_1': np.array([0.5, 0.5, -0.5]), 'E': np.array([0.5, 0.5, 0.5]), 'H': np.array([0.0, eta, 1.0 - nu]), 'H_1': np.array([0.0, 1.0 - eta, nu]), 'H_2': np.array([0.0, eta, -nu]), 'M': np.array([0.5, eta, 1.0 - nu]), 'M_1': np.array([0.5, 1 - eta, nu]), 'M_2': np.array([0.5, 1 - eta, nu]), 'X': np.array([0.0, 0.5, 0.0]), 'Y': np.array([0.0, 0.0, 0.5]), 'Y_1': np.array([0.0, 0.0, -0.5]), 'Z': np.array([0.5, 0.0, 0.0]) } path = [["\Gamma", "Y", "H", "C", "E", "M_1", "A", "X", "H_1"], ["M", "D", "Z"], ["Y", "D"]] return {'kpoints': kpoints, 'path': path} def mclc1(self, a, b, c, alpha): self.name = "MCLC1" zeta = (2 - b * cos(alpha) / c) / (4 * sin(alpha)**2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b psi = 0.75 - a**2 / (4 * b**2 * sin(alpha)**2) phi = psi + (0.75 - psi) * b * cos(alpha) / c kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'F': np.array([1 - zeta, 1 - zeta, 1 - eta]), 'F_1': np.array([zeta, zeta, eta]), 'F_2': np.array([-zeta, -zeta, 1 - eta]), #'F_3': np.array([1 - zeta, -zeta, 1 - eta]), 'I': np.array([phi, 1 - phi, 0.5]), 'I_1': np.array([1 - phi, phi - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'X': np.array([1 - psi, psi - 1, 0.0]), 'X_1': np.array([psi, 1 - psi, 0.0]), 'X_2': np.array([psi - 1, -psi, 0.0]), 'Y': np.array([0.5, 0.5, 0.0]), 'Y_1': np.array([-0.5, -0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "F_1"], ["Y", "X_1"], ["X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc2(self, a, b, c, alpha): self.name = "MCLC2" zeta = (2 - b * cos(alpha) / c) / (4 * sin(alpha)**2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b psi = 0.75 - a**2 / (4 * b**2 * sin(alpha)**2) phi = psi + (0.75 - psi) * b * cos(alpha) / c kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'F': np.array([1 - zeta, 1 - zeta, 1 - eta]), 'F_1': np.array([zeta, zeta, eta]), 'F_2': np.array([-zeta, -zeta, 1 - eta]), 'F_3': np.array([1 - zeta, -zeta, 1 - eta]), 'I': np.array([phi, 1 - phi, 0.5]), 'I_1': np.array([1 - phi, phi - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'X': np.array([1 - psi, psi - 1, 0.0]), 'X_1': np.array([psi, 1 - psi, 0.0]), 'X_2': np.array([psi - 1, -psi, 0.0]), 'Y': np.array([0.5, 0.5, 0.0]), 'Y_1': np.array([-0.5, -0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "F_1"], ["N", "\Gamma", "M"]] return {'kpoints': kpoints, 'path': path} def mclc3(self, a, b, c, alpha): self.name = "MCLC3" mu = (1 + b**2 / a**2) / 4.0 delta = b * c * cos(alpha) / (2 * a**2) zeta = mu - 0.25 + (1 - b * cos(alpha) / c)\ / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b phi = 1 + zeta - 2 * mu psi = eta - 2 * delta kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([1 - phi, 1 - phi, 1 - psi]), 'F_1': np.array([phi, phi - 1, psi]), 'F_2': np.array([1 - phi, -phi, 1 - psi]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([0.5, -0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\Gamma", "Y", "F", "H", "Z", "I", "F_1"], ["H_1", "Y_1", "X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc4(self, a, b, c, alpha): self.name = "MCLC4" mu = (1 + b**2 / a**2) / 4.0 delta = b * c * cos(alpha) / (2 * a**2) zeta = mu - 0.25 + (1 - b * cos(alpha) / c)\ / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b phi = 1 + zeta - 2 * mu psi = eta - 2 * delta kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([1 - phi, 1 - phi, 1 - psi]), 'F_1': np.array([phi, phi - 1, psi]), 'F_2': np.array([1 - phi, -phi, 1 - psi]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([0.5, -0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\Gamma", "Y", "F", "H", "Z", "I"], ["H_1", "Y_1", "X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc5(self, a, b, c, alpha): self.name = "MCLC5" zeta = (b**2 / a**2 + (1 - b * cos(alpha) / c) / sin(alpha)**2) / 4 eta = 0.5 + 2 * zeta * c * cos(alpha) / b mu = eta / 2 + b ** 2 / (4 * a ** 2) \ - b * c * cos(alpha) / (2 * a ** 2) nu = 2 * mu - zeta rho = 1 - zeta * a**2 / b**2 omega = (4 * nu - 1 - b ** 2 * sin(alpha) ** 2 / a ** 2)\ * c / (2 * b * cos(alpha)) delta = zeta * c * cos(alpha) / b + omega / 2 - 0.25 kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([nu, nu, omega]), 'F_1': np.array([1 - nu, 1 - nu, 1 - omega]), 'F_2': np.array([nu, nu - 1, omega]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([rho, 1 - rho, 0.5]), 'I_1': np.array([1 - rho, rho - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "H", "F_1"], ["H_1", "Y_1", "X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def tria(self): self.name = "TRI1a" kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([0.5, 0.5, 0.0]), 'M': np.array([0.0, 0.5, 0.5]), 'N': np.array([0.5, 0.0, 0.5]), 'R': np.array([0.5, 0.5, 0.5]), 'X': np.array([0.5, 0.0, 0.0]), 'Y': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5]) } path = [["X", "\Gamma", "Y"], ["L", "\Gamma", "Z"], ["N", "\Gamma", "M"], ["R", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def trib(self): self.name = "TRI1b" kpoints = { '\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([0.5, -0.5, 0.0]), 'M': np.array([0.0, 0.0, 0.5]), 'N': np.array([-0.5, -0.5, 0.5]), 'R': np.array([0.0, -0.5, 0.5]), 'X': np.array([0.0, -0.5, 0.0]), 'Y': np.array([0.5, 0.0, 0.0]), 'Z': np.array([-0.5, 0.0, 0.5]) } path = [["X", "\Gamma", "Y"], ["L", "\Gamma", "Z"], ["N", "\Gamma", "M"], ["R", "\Gamma"]] return {'kpoints': kpoints, 'path': path}
def drawkpt(struct, ndiv="10"): # symmetry information struct_sym = SpacegroupAnalyzer(struct) print("\nLattice details:") print("----------------") print("lattice type : {0}".format(struct_sym.get_lattice_type())) print( "space group : {0} ({1})".format( struct_sym.get_space_group_symbol(), struct_sym.get_space_group_number())) # Compute first brillouin zone ibz = HighSymmKpath(struct) print("ibz type : {0}".format(ibz.name)) [x, y, z] = list(map(list, zip(*ibz.get_kpoints()[0]))) fig = plt.figure("Brillouin Zone and High Symm Pts") ax = fig.gca(projection='3d') ax.plot(x, y, z) for i, name in enumerate(ibz.get_kpoints()[1]): if name != '': #print(" name {0} : [{1},{2},{3}]".format(name, x[i],y[i],z[i])) ax.text(x[i], y[i], z[i], '%s' % (name), color='k', size="15") new_lat = ibz.prim_rec bz_array = new_lat.get_wigner_seitz_cell() bz_faces = Poly3DCollection(bz_array) bz_faces.set_edgecolor('k') bz_faces.set_facecolor((0, 1, 1, 0.4)) ax.add_collection3d(bz_faces) ax.set_xlim(-1, 1) ax.set_ylim(-1, 1) ax.set_zlim(-1, 1) ax.set_xlabel('X') ax.set_ylabel('Y') ax.set_zlabel('Z') fig.suptitle( "Brillouin Zone and K_Path of \n {0}".format( struct.get_primitive_structure().formula)) fig.show() # if input("press [s]ave to save brillouin zone figure as it is \n") == "s": # fig.savefig("BZ_KPath.svg", bbox_inches='tight') # plt.close(fig) # print specific kpoints in the first brillouin zone print("\nList of high symmetry k-points:") print("-------------------------------") for key, val in ibz.kpath["kpoints"].items(): print("%8s %s" % (key, str(val))) # suggested path for the band structure print("\nSuggested paths in first brillouin zone:") print("----------------------------------------") for i, path in enumerate(ibz.kpath["path"]): print(" %2d:" % (i + 1), " -> ".join(path)) # write the KPOINTS file print("\nWrite file KPOINTS") kpt = Kpoints.automatic_linemode(ndiv, ibz) # if input("write kpt in cwd ?") == "Y": # kpt.write_file(os.path.join( # folder, "linear_KPOINTS")) return(kpt)
except (ValueError, IndexError): print("-d must be followed by an integer") exit(1) # read structure if os.path.exists(fstruct): struct = mg.Structure.from_file(fstruct) else: print("File %s does not exist" % fstruct) exit(1) # symmetry information struct_sym = SpacegroupAnalyzer(struct) print("\nLattice details:") print("----------------") print("lattice type : {0}".format(struct_sym.get_lattice_type())) print("space group : {0} ({1})".format(struct_sym.get_space_group_symbol(), struct_sym.get_space_group_number())) # Compute first brillouin zone ibz = HighSymmKpath(struct) print("ibz type : {0}".format(ibz.name)) #ibz.get_kpath_plot(savefig="path.png") # print specific kpoints in the first brillouin zone print("\nList of high symmetry k-points:") print("-------------------------------") for key, val in ibz.kpath["kpoints"].items(): print("%8s %s" % (key, str(val))) # suggested path for the band structure
class SpaceGroup(object): def __init__(self, configfile, symprec=0.01, angle_trelance=6): self.config_obj = ParseConfig(configfile) self.symprec = symprec self.angle_trelance = angle_trelance self.main() def set_structure(self): # # ======= ATOMIC POSITIONS ======= # a, b, c = self.config_obj.lattice_length[:3] alpha, beta, gamma = self.config_obj.lattice_angle[:3] lattice = mg.Lattice.from_parameters(a, b, c, alpha, beta, gamma) self.atoms = self.config_obj.atom_list atomic_positions = self.config_obj.atomic_position self.structure = mg.Structure(lattice, self.atoms, atomic_positions) def main(self): self.set_structure() # # generate instance for space group # self.spg = SpacegroupAnalyzer(self.structure, symprec=self.symprec, angle_tolerance=self.angle_trelance) def show_info(self): print('----- symmetrized structure(conventional unit cell) -----') print(self.spg.get_symmetrized_structure()) print() print('----- primitive structure -----') print(self.spg.find_primitive()) print() # # name of space group # print('--- infomation of space group ---') print(' HM symbol: {} '.format(self.spg.get_space_group_symbol())) print(' Space Group number = #{}'.format( self.spg.get_space_group_number())) print(' point group : {}'.format(self.spg.get_point_group_symbol())) print() print() print('--- crystal system ---') print(' crystal system:{}'.format(self.spg.get_crystal_system())) print(' lattice type:{}'.format(self.spg.get_lattice_type())) # # total data set # dataset = self.spg.get_symmetry_dataset() wyckoff_position = dataset['wyckoffs'] atom_pos = [] atom_name = [] wyckoff_data = [] for (i, wyckoff) in enumerate(wyckoff_position): aname = self.atoms[i] if aname not in atom_name or wyckoff not in atom_pos: info = { 'site_type_symbol': aname, 'wyckoff_letter': wyckoff, 'multiply': 0 } wyckoff_data.append(info) atom_pos.append(wyckoff) atom_name.append(aname) for (i, wyckoff) in enumerate(wyckoff_position): aname = self.atoms[i] for info in wyckoff_data: if info['site_type_symbol'] == aname: if info['wyckoff_letter'] == wyckoff: info['multiply'] += 1 print(' # of kinds of atoms = {}'.format(len(wyckoff_data))) print() for info in wyckoff_data: site_name = '{0}{1}-site'.format(info['multiply'], info['wyckoff_letter']) atom_name = info['site_type_symbol'] print(' atom:{0} wyckoff: {1}'.format(atom_name, site_name)) return def symmetrized(self): self.get_symmetrized_structure()
class HighSymmKpath(object): """ This class looks for path along high symmetry lines in the Brillouin Zone. It is based on Setyawan, W., & Curtarolo, S. (2010). High-throughput electronic band structure calculations: Challenges and tools. Computational Materials Science, 49(2), 299-312. doi:10.1016/j.commatsci.2010.05.010 The symmetry is determined by spglib through the SpacegroupAnalyzer class Args: structure (Structure): Structure object symprec (float): Tolerance for symmetry finding angle_tolerance (float): Angle tolerance for symmetry finding. """ def __init__(self, structure, symprec=0.01, angle_tolerance=5): self._structure = structure self._sym = SpacegroupAnalyzer(structure, symprec=symprec, angle_tolerance=angle_tolerance) self._prim = self._sym\ .get_primitive_standard_structure(international_monoclinic=False) self._conv = self._sym.get_conventional_standard_structure(international_monoclinic=False) self._prim_rec = self._prim.lattice.reciprocal_lattice self._kpath = None lattice_type = self._sym.get_lattice_type() spg_symbol = self._sym.get_spacegroup_symbol() if lattice_type == "cubic": if "P" in spg_symbol: self._kpath = self.cubic() elif "F" in spg_symbol: self._kpath = self.fcc() elif "I" in spg_symbol: self._kpath = self.bcc() else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "tetragonal": if "P" in spg_symbol: self._kpath = self.tet() elif "I" in spg_symbol: a = self._conv.lattice.abc[0] c = self._conv.lattice.abc[2] if c < a: self._kpath = self.bctet1(c, a) else: self._kpath = self.bctet2(c, a) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "orthorhombic": a = self._conv.lattice.abc[0] b = self._conv.lattice.abc[1] c = self._conv.lattice.abc[2] if "P" in spg_symbol: self._kpath = self.orc() elif "F" in spg_symbol: if 1 / a ** 2 > 1 / b ** 2 + 1 / c ** 2: self._kpath = self.orcf1(a, b, c) elif 1 / a ** 2 < 1 / b ** 2 + 1 / c ** 2: self._kpath = self.orcf2(a, b, c) else: self._kpath = self.orcf3(a, b, c) elif "I" in spg_symbol: self._kpath = self.orci(a, b, c) elif "C" in spg_symbol: self._kpath = self.orcc(a, b, c) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "hexagonal": self._kpath = self.hex() elif lattice_type == "rhombohedral": alpha = self._prim.lattice.lengths_and_angles[1][0] if alpha < 90: self._kpath = self.rhl1(alpha * pi / 180) else: self._kpath = self.rhl2(alpha * pi / 180) elif lattice_type == "monoclinic": a, b, c = self._conv.lattice.abc alpha = self._conv.lattice.lengths_and_angles[1][0] #beta = self._conv.lattice.lengths_and_angles[1][1] if "P" in spg_symbol: self._kpath = self.mcl(b, c, alpha * pi / 180) elif "C" in spg_symbol: kgamma = self._prim_rec.lengths_and_angles[1][2] if kgamma > 90: self._kpath = self.mclc1(a, b, c, alpha * pi / 180) if kgamma == 90: self._kpath = self.mclc2(a, b, c, alpha * pi / 180) if kgamma < 90: if b * cos(alpha * pi / 180) / c\ + b ** 2 * sin(alpha) ** 2 / a ** 2 < 1: self._kpath = self.mclc3(a, b, c, alpha * pi / 180) if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha) ** 2 / a ** 2 == 1: self._kpath = self.mclc4(a, b, c, alpha * pi / 180) if b * cos(alpha * pi / 180) / c \ + b ** 2 * sin(alpha) ** 2 / a ** 2 > 1: self._kpath = self.mclc5(a, b, c, alpha * pi / 180) else: warn("Unexpected value for spg_symbol: %s" % spg_symbol) elif lattice_type == "triclinic": kalpha = self._prim_rec.lengths_and_angles[1][0] kbeta = self._prim_rec.lengths_and_angles[1][1] kgamma = self._prim_rec.lengths_and_angles[1][2] if kalpha > 90 and kbeta > 90 and kgamma > 90: self._kpath = self.tria() if kalpha < 90 and kbeta < 90 and kgamma < 90: self._kpath = self.trib() if kalpha > 90 and kbeta > 90 and kgamma == 90: self._kpath = self.tria() if kalpha < 90 and kbeta < 90 and kgamma == 90: self._kpath = self.trib() else: warn("Unknown lattice type %s" % lattice_type) @property def structure(self): """ Returns: The standardized primitive structure """ return self._prim @property def kpath(self): """ Returns: The symmetry line path in reciprocal space """ return self._kpath def get_kpoints(self, line_density=20): """ Returns: the kpoints along the paths in cartesian coordinates together with the labels for symmetry points -Wei """ list_k_points = [] sym_point_labels = [] for b in self.kpath['path']: for i in range(1, len(b)): start = np.array(self.kpath['kpoints'][b[i - 1]]) end = np.array(self.kpath['kpoints'][b[i]]) distance = np.linalg.norm( self._prim_rec.get_cartesian_coords(start) - self._prim_rec.get_cartesian_coords(end)) nb = int(ceil(distance * line_density)) sym_point_labels.extend([b[i - 1]] + [''] * (nb - 1) + [b[i]]) list_k_points.extend( [self._prim_rec.get_cartesian_coords(start) + float(i) / float(nb) * (self._prim_rec.get_cartesian_coords(end) - self._prim_rec.get_cartesian_coords(start)) for i in range(0, nb + 1)]) return list_k_points, sym_point_labels def get_kpath_plot(self, **kwargs): """ Gives the plot (as a matplotlib object) of the symmetry line path in the Brillouin Zone. Returns: `matplotlib` figure. ================ ============================================================== kwargs Meaning ================ ============================================================== show True to show the figure (Default). savefig 'abc.png' or 'abc.eps'* to save the figure to a file. ================ ============================================================== """ import itertools import matplotlib.pyplot as plt from mpl_toolkits.mplot3d import axes3d def _plot_shape_skeleton(bz, style): for iface in range(len(bz)): for line in itertools.combinations(bz[iface], 2): for jface in range(len(bz)): if iface < jface and line[0] in bz[jface]\ and line[1] in bz[jface]: ax.plot([line[0][0], line[1][0]], [line[0][1], line[1][1]], [line[0][2], line[1][2]], style) def _plot_lattice(lattice): vertex1 = lattice.get_cartesian_coords([0.0, 0.0, 0.0]) vertex2 = lattice.get_cartesian_coords([1.0, 0.0, 0.0]) ax.plot([vertex1[0], vertex2[0]], [vertex1[1], vertex2[1]], [vertex1[2], vertex2[2]], color='g', linewidth=3) vertex2 = lattice.get_cartesian_coords([0.0, 1.0, 0.0]) ax.plot([vertex1[0], vertex2[0]], [vertex1[1], vertex2[1]], [vertex1[2], vertex2[2]], color='g', linewidth=3) vertex2 = lattice.get_cartesian_coords([0.0, 0.0, 1.0]) ax.plot([vertex1[0], vertex2[0]], [vertex1[1], vertex2[1]], [vertex1[2], vertex2[2]], color='g', linewidth=3) def _plot_kpath(kpath, lattice): for line in kpath['path']: for k in range(len(line) - 1): vertex1 = lattice.get_cartesian_coords(kpath['kpoints'] [line[k]]) vertex2 = lattice.get_cartesian_coords(kpath['kpoints'] [line[k + 1]]) ax.plot([vertex1[0], vertex2[0]], [vertex1[1], vertex2[1]], [vertex1[2], vertex2[2]], color='r', linewidth=3) def _plot_labels(kpath, lattice): for k in kpath['kpoints']: label = k if k.startswith("\\") or k.find("_") != -1: label = "$" + k + "$" off = 0.01 ax.text(lattice.get_cartesian_coords(kpath['kpoints'][k])[0] + off, lattice.get_cartesian_coords(kpath['kpoints'][k])[1] + off, lattice.get_cartesian_coords(kpath['kpoints'][k])[2] + off, label, color='b', size='25') ax.scatter([lattice.get_cartesian_coords( kpath['kpoints'][k])[0]], [lattice.get_cartesian_coords( kpath['kpoints'][k])[1]], [lattice.get_cartesian_coords( kpath['kpoints'][k])[2]], color='b') fig = plt.figure() ax = axes3d.Axes3D(fig) _plot_lattice(self._prim_rec) _plot_shape_skeleton(self._prim_rec.get_wigner_seitz_cell(), '-k') _plot_kpath(self.kpath, self._prim_rec) _plot_labels(self.kpath, self._prim_rec) ax.axis("off") show = kwargs.pop("show", True) if show: plt.show() savefig = kwargs.pop("savefig", None) if savefig: fig.savefig(savefig) return fig def cubic(self): self.name = "CUB" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'X': np.array([0.0, 0.5, 0.0]), 'R': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.5, 0.0])} path = [["\Gamma", "X", "M", "\Gamma", "R", "X"], ["M", "R"]] return {'kpoints': kpoints, 'path': path} def fcc(self): self.name = "FCC" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'K': np.array([3.0 / 8.0, 3.0 / 8.0, 3.0 / 4.0]), 'L': np.array([0.5, 0.5, 0.5]), 'U': np.array([5.0 / 8.0, 1.0 / 4.0, 5.0 / 8.0]), 'W': np.array([0.5, 1.0 / 4.0, 3.0 / 4.0]), 'X': np.array([0.5, 0.0, 0.5])} path = [["\Gamma", "X", "W", "K", "\Gamma", "L", "U", "W", "L", "K"], ["U", "X"]] return {'kpoints': kpoints, 'path': path} def bcc(self): self.name = "BCC" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'H': np.array([0.5, -0.5, 0.5]), 'P': np.array([0.25, 0.25, 0.25]), 'N': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "H", "N", "\Gamma", "P", "H"], ["P", "N"]] return {'kpoints': kpoints, 'path': path} def tet(self): self.name = "TET" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.5, 0.0]), 'R': np.array([0.0, 0.5, 0.5]), 'X': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "X", "M", "\Gamma", "Z", "R", "A", "Z"], ["X", "R"], ["M", "A"]] return {'kpoints': kpoints, 'path': path} def bctet1(self, c, a): self.name = "BCT1" eta = (1 + c ** 2 / a ** 2) / 4.0 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'M': np.array([-0.5, 0.5, 0.5]), 'N': np.array([0.0, 0.5, 0.0]), 'P': np.array([0.25, 0.25, 0.25]), 'X': np.array([0.0, 0.0, 0.5]), 'Z': np.array([eta, eta, -eta]), 'Z_1': np.array([-eta, 1 - eta, eta])} path = [["\Gamma", "X", "M", "\Gamma", "Z", "P", "N", "Z_1", "M"], ["X", "P"]] return {'kpoints': kpoints, 'path': path} def bctet2(self, c, a): self.name = "BCT2" eta = (1 + a ** 2 / c ** 2) / 4.0 zeta = a ** 2 / (2 * c ** 2) kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.0, 0.5, 0.0]), 'P': np.array([0.25, 0.25, 0.25]), '\Sigma': np.array([-eta, eta, eta]), '\Sigma_1': np.array([eta, 1 - eta, -eta]), 'X': np.array([0.0, 0.0, 0.5]), 'Y': np.array([-zeta, zeta, 0.5]), 'Y_1': np.array([0.5, 0.5, -zeta]), 'Z': np.array([0.5, 0.5, -0.5])} path = [["\Gamma", "X", "Y", "\Sigma", "\Gamma", "Z", "\Sigma_1", "N", "P", "Y_1", "Z"], ["X", "P"]] return {'kpoints': kpoints, 'path': path} def orc(self): self.name = "ORC" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'R': np.array([0.5, 0.5, 0.5]), 'S': np.array([0.5, 0.5, 0.0]), 'T': np.array([0.0, 0.5, 0.5]), 'U': np.array([0.5, 0.0, 0.5]), 'X': np.array([0.5, 0.0, 0.0]), 'Y': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "X", "S", "Y", "\Gamma", "Z", "U", "R", "T", "Z"], ["Y", "T"], ["U", "X"], ["S", "R"]] return {'kpoints': kpoints, 'path': path} def orcf1(self, a, b, c): self.name = "ORCF1" zeta = (1 + a ** 2 / b ** 2 - a ** 2 / c ** 2) / 4 eta = (1 + a ** 2 / b ** 2 + a ** 2 / c ** 2) / 4 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5 + zeta, zeta]), 'A_1': np.array([0.5, 0.5 - zeta, 1 - zeta]), 'L': np.array([0.5, 0.5, 0.5]), 'T': np.array([1, 0.5, 0.5]), 'X': np.array([0.0, eta, eta]), 'X_1': np.array([1, 1 - eta, 1 - eta]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0])} path = [["\Gamma", "Y", "T", "Z", "\Gamma", "X", "A_1", "Y"], ["T", "X_1"], ["X", "A", "Z"], ["L", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def orcf2(self, a, b, c): self.name = "ORCF2" phi = (1 + c ** 2 / b ** 2 - c ** 2 / a ** 2) / 4 eta = (1 + a ** 2 / b ** 2 - a ** 2 / c ** 2) / 4 delta = (1 + b ** 2 / a ** 2 - b ** 2 / c ** 2) / 4 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'C': np.array([0.5, 0.5 - eta, 1 - eta]), 'C_1': np.array([0.5, 0.5 + eta, eta]), 'D': np.array([0.5 - delta, 0.5, 1 - delta]), 'D_1': np.array([0.5 + delta, 0.5, delta]), 'L': np.array([0.5, 0.5, 0.5]), 'H': np.array([1 - phi, 0.5 - phi, 0.5]), 'H_1': np.array([phi, 0.5 + phi, 0.5]), 'X': np.array([0.0, 0.5, 0.5]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0])} path = [["\Gamma", "Y", "C", "D", "X", "\Gamma", "Z", "D_1", "H", "C"], ["C_1", "Z"], ["X", "H_1"], ["H", "Y"], ["L", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def orcf3(self, a, b, c): self.name = "ORCF3" zeta = (1 + a ** 2 / b ** 2 - a ** 2 / c ** 2) / 4 eta = (1 + a ** 2 / b ** 2 + a ** 2 / c ** 2) / 4 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5 + zeta, zeta]), 'A_1': np.array([0.5, 0.5 - zeta, 1 - zeta]), 'L': np.array([0.5, 0.5, 0.5]), 'T': np.array([1, 0.5, 0.5]), 'X': np.array([0.0, eta, eta]), 'X_1': np.array([1, 1 - eta, 1 - eta]), 'Y': np.array([0.5, 0.0, 0.5]), 'Z': np.array([0.5, 0.5, 0.0])} path = [["\Gamma", "Y", "T", "Z", "\Gamma", "X", "A_1", "Y"], ["X", "A", "Z"], ["L", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def orci(self, a, b, c): self.name = "ORCI" zeta = (1 + a ** 2 / c ** 2) / 4 eta = (1 + b ** 2 / c ** 2) / 4 delta = (b ** 2 - a ** 2) / (4 * c ** 2) mu = (a ** 2 + b ** 2) / (4 * c ** 2) kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([-mu, mu, 0.5 - delta]), 'L_1': np.array([mu, -mu, 0.5 + delta]), 'L_2': np.array([0.5 - delta, 0.5 + delta, -mu]), 'R': np.array([0.0, 0.5, 0.0]), 'S': np.array([0.5, 0.0, 0.0]), 'T': np.array([0.0, 0.0, 0.5]), 'W': np.array([0.25, 0.25, 0.25]), 'X': np.array([-zeta, zeta, zeta]), 'X_1': np.array([zeta, 1 - zeta, -zeta]), 'Y': np.array([eta, -eta, eta]), 'Y_1': np.array([1 - eta, eta, -eta]), 'Z': np.array([0.5, 0.5, -0.5])} path = [["\Gamma", "X", "L", "T", "W", "R", "X_1", "Z", "\Gamma", "Y", "S", "W"], ["L_1", "Y"], ["Y_1", "Z"]] return {'kpoints': kpoints, 'path': path} def orcc(self, a, b, c): self.name = "ORCC" zeta = (1 + a ** 2 / b ** 2) / 4 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([zeta, zeta, 0.5]), 'A_1': np.array([-zeta, 1 - zeta, 0.5]), 'R': np.array([0.0, 0.5, 0.5]), 'S': np.array([0.0, 0.5, 0.0]), 'T': np.array([-0.5, 0.5, 0.5]), 'X': np.array([zeta, zeta, 0.0]), 'X_1': np.array([-zeta, 1 - zeta, 0.0]), 'Y': np.array([-0.5, 0.5, 0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "X", "S", "R", "A", "Z", "\Gamma", "Y", "X_1", "A_1", "T", "Y"], ["Z", "T"]] return {'kpoints': kpoints, 'path': path} def hex(self): self.name = "HEX" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.0, 0.0, 0.5]), 'H': np.array([1.0 / 3.0, 1.0 / 3.0, 0.5]), 'K': np.array([1.0 / 3.0, 1.0 / 3.0, 0.0]), 'L': np.array([0.5, 0.0, 0.5]), 'M': np.array([0.5, 0.0, 0.0])} path = [["\Gamma", "M", "K", "\Gamma", "A", "L", "H", "A"], ["L", "M"], ["K", "H"]] return {'kpoints': kpoints, 'path': path} def rhl1(self, alpha): self.name = "RHL1" eta = (1 + 4 * cos(alpha)) / (2 + 4 * cos(alpha)) nu = 3.0 / 4.0 - eta / 2.0 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'B': np.array([eta, 0.5, 1.0 - eta]), 'B_1': np.array([1.0 / 2.0, 1.0 - eta, eta - 1.0]), 'F': np.array([0.5, 0.5, 0.0]), 'L': np.array([0.5, 0.0, 0.0]), 'L_1': np.array([0.0, 0.0, -0.5]), 'P': np.array([eta, nu, nu]), 'P_1': np.array([1.0 - nu, 1.0 - nu, 1.0 - eta]), 'P_2': np.array([nu, nu, eta - 1.0]), 'Q': np.array([1.0 - nu, nu, 0.0]), 'X': np.array([nu, 0.0, -nu]), 'Z': np.array([0.5, 0.5, 0.5])} path = [["\Gamma", "L", "B_1"], ["B", "Z", "\Gamma", "X"], ["Q", "F", "P_1", "Z"], ["L", "P"]] return {'kpoints': kpoints, 'path': path} def rhl2(self, alpha): self.name = "RHL2" eta = 1 / (2 * tan(alpha / 2.0) ** 2) nu = 3.0 / 4.0 - eta / 2.0 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([0.5, -0.5, 0.0]), 'L': np.array([0.5, 0.0, 0.0]), 'P': np.array([1 - nu, -nu, 1 - nu]), 'P_1': np.array([nu, nu - 1.0, nu - 1.0]), 'Q': np.array([eta, eta, eta]), 'Q_1': np.array([1.0 - eta, -eta, -eta]), 'Z': np.array([0.5, -0.5, 0.5])} path = [["\Gamma", "P", "Z", "Q", "\Gamma", "F", "P_1", "Q_1", "L", "Z"]] return {'kpoints': kpoints, 'path': path} def mcl(self, b, c, beta): self.name = "MCL" eta = (1 - b * cos(beta) / c) / (2 * sin(beta) ** 2) nu = 0.5 - eta * c * cos(beta) / b kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'A': np.array([0.5, 0.5, 0.0]), 'C': np.array([0.0, 0.5, 0.5]), 'D': np.array([0.5, 0.0, 0.5]), 'D_1': np.array([0.5, 0.5, -0.5]), 'E': np.array([0.5, 0.5, 0.5]), 'H': np.array([0.0, eta, 1.0 - nu]), 'H_1': np.array([0.0, 1.0 - eta, nu]), 'H_2': np.array([0.0, eta, -nu]), 'M': np.array([0.5, eta, 1.0 - nu]), 'M_1': np.array([0.5, 1 - eta, nu]), 'M_2': np.array([0.5, 1 - eta, nu]), 'X': np.array([0.0, 0.5, 0.0]), 'Y': np.array([0.0, 0.0, 0.5]), 'Y_1': np.array([0.0, 0.0, -0.5]), 'Z': np.array([0.5, 0.0, 0.0])} path = [["\Gamma", "Y", "H", "C", "E", "M_1", "A", "X", "H_1"], ["M", "D", "Z"], ["Y", "D"]] return {'kpoints': kpoints, 'path': path} def mclc1(self, a, b, c, alpha): self.name = "MCLC1" zeta = (2 - b * cos(alpha) / c) / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b psi = 0.75 - a ** 2 / (4 * b ** 2 * sin(alpha) ** 2) phi = psi + (0.75 - psi) * b * cos(alpha) / c kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'F': np.array([1 - zeta, 1 - zeta, 1 - eta]), 'F_1': np.array([zeta, zeta, eta]), 'F_2': np.array([-zeta, -zeta, 1 - eta]), #'F_3': np.array([1 - zeta, -zeta, 1 - eta]), 'I': np.array([phi, 1 - phi, 0.5]), 'I_1': np.array([1 - phi, phi - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'X': np.array([1 - psi, psi - 1, 0.0]), 'X_1': np.array([psi, 1 - psi, 0.0]), 'X_2': np.array([psi - 1, -psi, 0.0]), 'Y': np.array([0.5, 0.5, 0.0]), 'Y_1': np.array([-0.5, -0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "F_1"], ["Y", "X_1"], ["X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc2(self, a, b, c, alpha): self.name = "MCLC2" zeta = (2 - b * cos(alpha) / c) / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b psi = 0.75 - a ** 2 / (4 * b ** 2 * sin(alpha) ** 2) phi = psi + (0.75 - psi) * b * cos(alpha) / c kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'F': np.array([1 - zeta, 1 - zeta, 1 - eta]), 'F_1': np.array([zeta, zeta, eta]), 'F_2': np.array([-zeta, -zeta, 1 - eta]), 'F_3': np.array([1 - zeta, -zeta, 1 - eta]), 'I': np.array([phi, 1 - phi, 0.5]), 'I_1': np.array([1 - phi, phi - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'X': np.array([1 - psi, psi - 1, 0.0]), 'X_1': np.array([psi, 1 - psi, 0.0]), 'X_2': np.array([psi - 1, -psi, 0.0]), 'Y': np.array([0.5, 0.5, 0.0]), 'Y_1': np.array([-0.5, -0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "F_1"], ["N", "\Gamma", "M"]] return {'kpoints': kpoints, 'path': path} def mclc3(self, a, b, c, alpha): self.name = "MCLC3" mu = (1 + b ** 2 / a ** 2) / 4.0 delta = b * c * cos(alpha) / (2 * a ** 2) zeta = mu - 0.25 + (1 - b * cos(alpha) / c)\ / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b phi = 1 + zeta - 2 * mu psi = eta - 2 * delta kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([1 - phi, 1 - phi, 1 - psi]), 'F_1': np.array([phi, phi - 1, psi]), 'F_2': np.array([1 - phi, -phi, 1 - psi]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([0.5, -0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "Y", "F", "H", "Z", "I", "F_1"], ["H_1", "Y_1", "X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc4(self, a, b, c, alpha): self.name = "MCLC4" mu = (1 + b ** 2 / a ** 2) / 4.0 delta = b * c * cos(alpha) / (2 * a ** 2) zeta = mu - 0.25 + (1 - b * cos(alpha) / c)\ / (4 * sin(alpha) ** 2) eta = 0.5 + 2 * zeta * c * cos(alpha) / b phi = 1 + zeta - 2 * mu psi = eta - 2 * delta kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([1 - phi, 1 - phi, 1 - psi]), 'F_1': np.array([phi, phi - 1, psi]), 'F_2': np.array([1 - phi, -phi, 1 - psi]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([0.5, -0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "Y", "F", "H", "Z", "I"], ["H_1", "Y_1", "X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def mclc5(self, a, b, c, alpha): self.name = "MCLC5" zeta = (b ** 2 / a ** 2 + (1 - b * cos(alpha) / c) / sin(alpha) ** 2) / 4 eta = 0.5 + 2 * zeta * c * cos(alpha) / b mu = eta / 2 + b ** 2 / (4 * a ** 2) \ - b * c * cos(alpha) / (2 * a ** 2) nu = 2 * mu - zeta rho = 1 - zeta * a ** 2 / b ** 2 omega = (4 * nu - 1 - b ** 2 * sin(alpha) ** 2 / a ** 2)\ * c / (2 * b * cos(alpha)) delta = zeta * c * cos(alpha) / b + omega / 2 - 0.25 kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'F': np.array([nu, nu, omega]), 'F_1': np.array([1 - nu, 1 - nu, 1 - omega]), 'F_2': np.array([nu, nu - 1, omega]), 'H': np.array([zeta, zeta, eta]), 'H_1': np.array([1 - zeta, -zeta, 1 - eta]), 'H_2': np.array([-zeta, -zeta, 1 - eta]), 'I': np.array([rho, 1 - rho, 0.5]), 'I_1': np.array([1 - rho, rho - 1, 0.5]), 'L': np.array([0.5, 0.5, 0.5]), 'M': np.array([0.5, 0.0, 0.5]), 'N': np.array([0.5, 0.0, 0.0]), 'N_1': np.array([0.0, -0.5, 0.0]), 'X': np.array([0.5, -0.5, 0.0]), 'Y': np.array([mu, mu, delta]), 'Y_1': np.array([1 - mu, -mu, -delta]), 'Y_2': np.array([-mu, -mu, -delta]), 'Y_3': np.array([mu, mu - 1, delta]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["\Gamma", "Y", "F", "L", "I"], ["I_1", "Z", "H", "F_1"], ["H_1", "Y_1", "X", "\Gamma", "N"], ["M", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def tria(self): self.name = "TRI1a" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([0.5, 0.5, 0.0]), 'M': np.array([0.0, 0.5, 0.5]), 'N': np.array([0.5, 0.0, 0.5]), 'R': np.array([0.5, 0.5, 0.5]), 'X': np.array([0.5, 0.0, 0.0]), 'Y': np.array([0.0, 0.5, 0.0]), 'Z': np.array([0.0, 0.0, 0.5])} path = [["X", "\Gamma", "Y"], ["L", "\Gamma", "Z"], ["N", "\Gamma", "M"], ["R", "\Gamma"]] return {'kpoints': kpoints, 'path': path} def trib(self): self.name = "TRI1b" kpoints = {'\Gamma': np.array([0.0, 0.0, 0.0]), 'L': np.array([0.5, -0.5, 0.0]), 'M': np.array([0.0, 0.0, 0.5]), 'N': np.array([-0.5, -0.5, 0.5]), 'R': np.array([0.0, -0.5, 0.5]), 'X': np.array([0.0, -0.5, 0.0]), 'Y': np.array([0.5, 0.0, 0.0]), 'Z': np.array([-0.5, 0.0, 0.5])} path = [["X", "\Gamma", "Y"], ["L", "\Gamma", "Z"], ["N", "\Gamma", "M"], ["R", "\Gamma"]] return {'kpoints': kpoints, 'path': path}
def __init__(self, structure: Structure, conventional_base: bool = True, max_num_atoms: int = 400, min_num_atoms: int = 50, criterion: float = 0.12, rhombohedral_angle: float = 70, symprec: float = SYMMETRY_TOLERANCE, angle_tolerance: float = ANGLE_TOL): """Constructs a set of supercells satisfying an isotropic criterion. Args: structure (pmg structure class object): Unitcell structure conventional_base (bool): Conventional cell is expanded when True, otherwise primitive cell is expanded. max_num_atoms (int): Maximum number of atoms in the supercell. min_num_atoms (int): Minimum number of atoms in the supercell. criterion (float): Criterion to judge if a supercell is isotropic or not. rhombohedral_angle (float): Rhombohedral primitive cells may have very small or very large lattice angles not suited for first-principles calculations. Therefore, only the supercells with rhombohedral_angle <= lattice angle <= 180 - rhombohedral_angle are returned. Then, the new supercells are iteratively created by multiplying [[1, 1, -1], [-1, 1, 1], [1, -1, 1]] or [[1, 1, 0], [0, 1, 1], [1, 0, 1]]. symprec (float): Precision used for symmetry analysis in angstrom. angle_tolerance (float): Angle tolerance for symmetry analysis in degree. """ primitive_cell, _ = \ find_spglib_primitive(structure, symprec, angle_tolerance) if max_num_atoms < len(primitive_cell): raise CellSizeError("Number of atoms in unitcell is too large.") self.unitcell = primitive_cell.get_sorted_structure() sga = SpacegroupAnalyzer(structure, symprec, angle_tolerance) symmetry_dataset = sga.get_symmetry_dataset() logger.info(f"Space group: {symmetry_dataset['international']}") self.conventional_base = conventional_base lattice = sga.get_lattice_type() centering = symmetry_dataset["international"][0] if conventional_base: to_unitcell_mat = transmat_primitive2standard(centering) rhombohedral = False tetragonal = lattice == "tetragonal" else: to_unitcell_mat = np.eye(3, dtype=int) rhombohedral = lattice == "rhombohedral" if lattice == "tetragonal" and centering == "P": tetragonal = True else: tetragonal = False self.supercells = [] # Isotropically incremented matrix one by one trans_mat = to_unitcell_mat incremented_mat = np.eye(3, dtype=int) rotation_matrix = np.eye(3, dtype=int) for i in range(int(max_num_atoms / len(primitive_cell))): isotropy, angle = calc_isotropy(self.unitcell, trans_mat) # int is needed when numpy.float is rounded. multiplicity = int(round(np.linalg.det(trans_mat))) num_atoms = multiplicity * len(primitive_cell) if num_atoms > max_num_atoms: break if isotropy < criterion and num_atoms >= min_num_atoms: self.supercells.append( Supercell(self.unitcell, trans_mat, multiplicity)) rhombohedral_shape = None if rhombohedral: if angle < rhombohedral_angle: rhombohedral_shape = "sharp" elif angle > 180 - rhombohedral_angle: rhombohedral_shape = "blunt" if rhombohedral_shape == "sharp": m = np.array([[1, 1, -1], [-1, 1, 1], [1, -1, 1]]) rotation_matrix = np.dot(rotation_matrix, m) elif rhombohedral_shape == "blunt": m = np.array([[1, 1, 0], [0, 1, 1], [1, 0, 1]]) rotation_matrix = np.dot(rotation_matrix, m) else: if tetragonal: s = self.unitcell * trans_mat if s.lattice.a < s.lattice.c: if rotation_matrix[0, 1] == 0: a = incremented_mat[0, 0] if (a + 1)**2 < a**2 * 2: incremented_mat[0, 0] += 1 incremented_mat[1, 1] += 1 else: rotation_matrix = \ np.array([[1, 1, 0], [-1, 1, 0], [0, 0, 1]]) else: incremented_mat[0, 0] += 1 incremented_mat[1, 1] += 1 rotation_matrix = np.eye(3, dtype=int) incremented_mat *= rotation_matrix else: incremented_mat[2, 2] += 1 else: super_abc = (self.unitcell * trans_mat).lattice.abc # multi indices within 1.05a, where a is the shortest # supercell lattice length, are incremented simultaneously. for j in range(3): if super_abc[j] / min(super_abc) < 1.05: incremented_mat[j, j] += 1 trans_mat = np.dot(np.dot(incremented_mat, rotation_matrix), to_unitcell_mat)
def calc_shiftk(structure, symprec=0.01, angle_tolerance=5): """ Find the values of ``shiftk`` and ``nshiftk`` appropriated for the sampling of the Brillouin zone. When the primitive vectors of the lattice do NOT form a FCC or a BCC lattice, the usual (shifted) Monkhorst-Pack grids are formed by using nshiftk=1 and shiftk 0.5 0.5 0.5 . This is often the preferred k point sampling. For a non-shifted Monkhorst-Pack grid, use `nshiftk=1` and `shiftk 0.0 0.0 0.0`, but there is little reason to do that. When the primitive vectors of the lattice form a FCC lattice, with rprim:: 0.0 0.5 0.5 0.5 0.0 0.5 0.5 0.5 0.0 the (very efficient) usual Monkhorst-Pack sampling will be generated by using nshiftk= 4 and shiftk:: 0.5 0.5 0.5 0.5 0.0 0.0 0.0 0.5 0.0 0.0 0.0 0.5 When the primitive vectors of the lattice form a BCC lattice, with rprim:: -0.5 0.5 0.5 0.5 -0.5 0.5 0.5 0.5 -0.5 the usual Monkhorst-Pack sampling will be generated by using nshiftk= 2 and shiftk:: 0.25 0.25 0.25 -0.25 -0.25 -0.25 However, the simple sampling nshiftk=1 and shiftk 0.5 0.5 0.5 is excellent. For hexagonal lattices with hexagonal axes, e.g. rprim:: 1.0 0.0 0.0 -0.5 sqrt(3)/2 0.0 0.0 0.0 1.0 one can use nshiftk= 1 and shiftk 0.0 0.0 0.5 In rhombohedral axes, e.g. using angdeg 3*60., this corresponds to shiftk 0.5 0.5 0.5, to keep the shift along the symmetry axis. Returns: Suggested value of shiftk. """ # Find lattice type. from pymatgen.symmetry.analyzer import SpacegroupAnalyzer sym = SpacegroupAnalyzer(structure, symprec=symprec, angle_tolerance=angle_tolerance) lattice_type, spg_symbol = sym.get_lattice_type( ), sym.get_space_group_symbol() # Check if the cell is primitive is_primitive = len(sym.find_primitive()) == len(structure) # Generate the appropriate set of shifts. shiftk = None if is_primitive: if lattice_type == "cubic": if "F" in spg_symbol: # FCC shiftk = [ 0.5, 0.5, 0.5, 0.5, 0.0, 0.0, 0.0, 0.5, 0.0, 0.0, 0.0, 0.5 ] elif "I" in spg_symbol: # BCC shiftk = [0.25, 0.25, 0.25, -0.25, -0.25, -0.25] # shiftk = [0.5, 0.5, 05]) elif lattice_type == "hexagonal": # Find the hexagonal axis and set the shift along it. for i, angle in enumerate(structure.lattice.angles): if abs(angle - 120) < 1.0: j = (i + 1) % 3 k = (i + 2) % 3 hex_ax = [ax for ax in range(3) if ax not in [j, k]][0] break else: raise ValueError("Cannot find hexagonal axis") shiftk = [0.0, 0.0, 0.0] shiftk[hex_ax] = 0.5 elif lattice_type == "tetragonal": if "I" in spg_symbol: # BCT shiftk = [0.25, 0.25, 0.25, -0.25, -0.25, -0.25] if shiftk is None: # Use default value. shiftk = [0.5, 0.5, 0.5] return np.reshape(shiftk, (-1, 3))
class SpaceGroup(object): def __init__(self, configfile, symprec=0.01, angle_trelance=6): self.config_obj = ParseConfig(configfile) self.symprec = symprec self.angle_trelance = angle_trelance self.main() def set_structure(self): # # ======= ATOMIC POSITIONS ======= # a, b, c = self.config_obj.lattice_length[:3] alpha, beta, gamma = self.config_obj.lattice_angle[:3] lattice = mg.Lattice.from_parameters(a, b, c, alpha, beta, gamma) self.atoms = self.config_obj.atom_list atomic_positions = self.config_obj.atomic_position self.structure = mg.Structure(lattice, self.atoms, atomic_positions) def main(self): self.set_structure() # # generate instance for space group # self.spg = SpacegroupAnalyzer(self.structure, symprec=self.symprec, angle_tolerance=self.angle_trelance) try: self.hmname = self.spg.get_space_group_symbol() self.ispg = self.spg.get_space_group_number() except TypeError: print() print(' **** INTERNAL LIBRARY WARNING ****') print(' pymatgen and spglib cannot identify space group', end='') print(' for smaller primitive cell.') print(' we expect this bug will be fixed near future.', end='') print('metis uses original primitive cell.') self.spg = None self.hmname = None self.ispg = None def generate_primitive_lattice(self): # # in this case, spglib cannot identify space group # if self.spg is None: return my_data = str(self.spg.find_primitive()) data_region = False atomic_positions = [] for line in my_data.split('\n'): linebuf = line.strip() if re.search('^abc\s+:', linebuf): lattice_length = \ [float(x) for x in linebuf.split(':')[1].split()] if re.search('^angles:', linebuf): lattice_angle = \ [float(x) for x in linebuf.split(':')[1].split()] if re.search('^#', linebuf) and 'SP' in linebuf: data_region = True continue if data_region: if re.search('^---', linebuf): continue element = linebuf.split()[1] pos = [float(x) for x in linebuf.split()[2:]] info = {'element': element, 'position': pos} atomic_positions.append(info) lattice_type = self.hmname[0] compound_name = self.get_compound_name(atomic_positions) return {'ispg': self.ispg, 'hmname': self.hmname, 'lattice_length': lattice_length, 'lattice_angle': lattice_angle, 'lattice_type': lattice_type, 'atomic_positions': atomic_positions, 'compound_name': compound_name} def get_compound_name(self, atomic_positions): natoms = None compound = '' pre_element = None for atom in atomic_positions: element = atom['element'] if pre_element != element: if pre_element is not None: compound += str(natoms) compound += element natoms = 1 pre_element = element else: natoms += 1 compound += str(natoms) return compound def show_info(self): print('----- symmetrized structure(conventional unit cell) -----') print(self.spg.get_symmetrized_structure()) print() print('----- primitive structure -----') print(self.spg.find_primitive()) print() # # name of space group # print('--- infomation of space group ---') print(' HM symbol: {} '.format(self.hmname)) print(' Space Group number = #{}'.format(self.ispg)) print(' point group : {}'.format(self.spg.get_point_group_symbol())) print() print() print('--- crystal system ---') print(' crystal system:{}'.format(self.spg.get_crystal_system())) print(' lattice type:{}'.format(self.spg.get_lattice_type())) print() # # total data set # dataset = self.spg.get_symmetry_dataset() wyckoff_position = dataset['wyckoffs'] atom_pos = [] atom_name = [] wyckoff_data = [] for (i, wyckoff) in enumerate(wyckoff_position): aname = self.atoms[i] if aname not in atom_name or wyckoff not in atom_pos: info = {'site_type_symbol': aname, 'wyckoff_letter': wyckoff, 'multiply': 0} wyckoff_data.append(info) atom_pos.append(wyckoff) atom_name.append(aname) for (i, wyckoff) in enumerate(wyckoff_position): aname = self.atoms[i] for info in wyckoff_data: if info['site_type_symbol'] == aname: if info['wyckoff_letter'] == wyckoff: info['multiply'] += 1 print(' # of kinds of atoms = {}'.format(len(wyckoff_data))) print() for info in wyckoff_data: site_name = '{0}{1}-site'.format(info['multiply'], info['wyckoff_letter']) atom_name = info['site_type_symbol'] print(' atom:{0} wyckoff: {1}'.format(atom_name, site_name)) return def get_conventional_cell(self): # # infomation of original primitive cell # self.prim_atom_info = {} data_set = self.spg.get_symmetry_dataset() wyckoffs = data_set['wyckoffs'] natoms = len(self.atoms) atom_info_tmp = [] for iatom in range(natoms): element = self.atoms[iatom], wyckoff_letter = wyckoffs[iatom] info = {'element': self.atoms[iatom], 'wyckoff_letter': wyckoffs[iatom]} atom_info_tmp.append(info) element_list = [] atom_info = [] for info in atom_info_tmp: element = info['element'] wyckoff_letter = info['wyckoff_letter'] if element not in element_list: element_list.append(element) info = {} info['element'] = element info['wyckoff_letter'] = [wyckoff_letter] atom_info.append(info) else: atom_info[-1]['wyckoff_letter'].append(wyckoff_letter) self.primitive_cell_info = {'ispg': self.ispg, 'natoms': natoms, 'atom_info': atom_info} # # conventional unit cell # data = str(self.spg.get_conventional_standard_structure()) data_set = self.spg.get_symmetry_dataset() wyckoffs = data_set['wyckoffs'] data_region = False atom_info = [] self.atoms = [] atomic_positions = [] for line in data.split('\n'): linebuf = line.strip() if re.search('abc\s+:', linebuf): lattice_length = \ [float(x) for x in linebuf.split(':')[1].split()] if re.search('angles\s*:', linebuf): lattice_angle = \ [float(x) for x in linebuf.split(':')[1].split()] if re.search('^#\s+SP', linebuf): data_region = True continue if data_region: if re.search('^---', linebuf): continue data_line = linebuf.split() element = data_line[1] position = [float(x) for x in data_line[2:]] self.atoms.append(element) atomic_positions.append(position) # # generate conventional infomation # a, b, c = lattice_length alpha, beta, gamma = lattice_angle lattice = mg.Lattice.from_parameters(a, b, c, alpha, beta, gamma) try: self.structure = mg.Structure(lattice, self.atoms, atomic_positions) self.spg = SpacegroupAnalyzer(self.structure, symprec=self.symprec, angle_tolerance=self.angle_trelance) self.ispg = self.spg.get_space_group_number() self.hmname = self.spg.get_space_group_symbol() except TypeError: print() print(' **** INTERNAL LIBRARY WARNING ****') print(' pymatgen and spglib cannot identify space group', end='') print(' for smaller primitive cell.') print(' we expect this bug will be fixed near future.', end='') print(' metis uses original primitive cell.') self.spg = None self.ispg = None self.hmname = None return self def symmetrized(self): self.get_symmetrized_structure()