oI2

Reference

POSCAR files with the crystal structure for these examples are taken from the seekpath repository with the permission of its authors. We refer you to seekpath for the original copies of the files and the license for those. To read more about the extended Bravais lattice symbols, chosen high-symmetry points and k-paths we refer you to the HPKOT paper.

Getting an example

To get an example crystal use wulfric.crystal.hpkot_get_example().

import wulfric

# For every extended bravais lattice symbol two examples are defined:
# with and without inversion symmetry.
cell, atoms = wulfric.crystal.hpkot_get_example(
    extended_bl_symbol="oI2", with_inversion=False
)

# To avoid multiple calls to spglib one can do it once and then pass spglib_data
# to the functions where it is needed
spglib_data = wulfric.get_spglib_data(cell=cell, atoms=atoms)

kp = wulfric.Kpoints.from_crystal(
    cell=cell, atoms=atoms, convention="HPKOT", with_time_reversal=True
)

kp_no_tr = wulfric.Kpoints.from_crystal(
    cell=cell, atoms=atoms, convention="HPKOT", with_time_reversal=False
)

conv_cell, conv_atoms = wulfric.crystal.get_conventional(
    cell=cell, atoms=atoms, convention="HPKOT", spglib_data=spglib_data
)

prim_cell, prim_atoms = wulfric.crystal.get_primitive(
    cell=cell, atoms=atoms, convention="HPKOT", spglib_data=spglib_data
)

K-path

print(kp.path_string)

GAMMA-X-U2|Y0-GAMMA-LAMBDA0|G2-X|GAMMA-R-W-S-GAMMA-T-W

High-symmetry points

print(kp.hs_table(decimals=4))

Name      rel_b1  rel_b2  rel_b3      k_x     k_y     k_z
GAMMA     0.0000  0.0000  0.0000   0.0000  0.0000  0.0000
X         1.0000  0.0000  0.0000   0.6374  0.0000  0.0000
S         0.0000  0.5000  0.5000   0.0000  0.4561  0.4482
R         0.5000  0.0000  0.5000   0.3187  0.0000  0.4482
T         0.5000  0.5000  0.0000   0.3187  0.4561  0.0000
W         0.5000  0.5000  0.5000   0.3187  0.4561  0.4482
Y0        0.0000  0.7441  0.0000   0.0000  0.6788  0.0000
U2        1.0000  0.2559 -0.0000   0.6374  0.2334 -0.0000
LAMBDA0   0.0000 -0.0000  0.7527   0.0000 -0.0000  0.6748
G2        1.0000  0.0000  0.2473   0.6374  0.0000  0.2217
K        -0.0000  0.7441  0.2473  -0.0000  0.6788  0.2217
K2        0.0000  0.2559  0.7527   0.0000  0.2334  0.6748
K4        1.0000  0.2559  0.2473   0.6374  0.2334  0.2217

Brillouin zone and default k-path

pe = wulfric.PlotlyEngine(_sphinx_gallery_fix=True)

pe.plot_brillouin_zone(
    cell=prim_cell, color="red", legend_label="Brillouin zone of the primitive cell"
)
pe.plot_brillouin_zone(
    cell=cell, color="chocolate", legend_label="Brillouin zone of the original cell"
)
pe.plot_kpath(kp=kp, legend_group="with TR", legend_label="With time-reversal")
pe.plot_kpoints(kp=kp, only_from_kpath=True, legend_group="with TR")

pe.plot_kpath(
    kp=kp_no_tr,
    color="#7D7D7D",
    legend_group="without TR",
    legend_label="Without time-reversal",
)
pe.plot_kpoints(
    kp=kp_no_tr, only_from_kpath=True, color="#7D7D7D", legend_group="without TR"
)

pe.show(axes_visible=False)

Cells of real space

pe = wulfric.PlotlyEngine(_sphinx_gallery_fix=True)

pe.plot_cell(cell=cell, legend_label="Original cell", color="Chocolate")
pe.plot_cell(cell=prim_cell, legend_label="Primitive cell", color="Black")
pe.plot_cell(cell=conv_cell, legend_label="Conventional cell", color="Blue")
pe.plot_wigner_seitz_cell(
    cell=prim_cell, legend_label="Wigner-Seitz cell", color="green"
)

pe.show(axes_visible=False)