MCLC2

Base-centered monoclinic cell is defined by four parameters \(a\), \(b\), \(c\) and \(\alpha\) with \(b \le c\), \(\alpha < 90^{\circ}\).

MCLC lattice has variation MCLC2 when \(k_{\gamma} = 90^{\circ}\).

Cell constructor

To get an example of the cell use wulfric.cell.SC_MCLC().

wulfric.cell.sc_get_example() returns an example where \(a = 1.4\cdot\pi\cdot\sin(75^{\circ})\), \(b = 1.4\cdot\pi\), \(c = 1.7\cdot\pi\) and \(\alpha=75^{\circ}\).

import wulfric

cell = wulfric.cell.sc_get_example("MCLC2")
atoms = dict(positions=[[0, 0, 0]], spglib_types=[1])

# 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="SC")

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

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

variation = wulfric.crystal.sc_get_variation(
    cell=cell, atoms=atoms, spglib_data=spglib_data
)

assert variation == "MCLC2"

print(variation)

MCLC2

K-path

print(kp.path_string)

GAMMA-Y-F-L-I|I1-Z-F1|N-GAMMA-M

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
N       0.0000 -0.5000 -0.0000   0.7395 -0.7143  0.1914
N1      0.5000 -0.0000  0.0000   0.7395  0.7143 -0.1914
F      -0.5212 -0.5212 -0.1991  -0.0000 -1.4892  0.1566
F1     -0.4788 -0.4788 -0.8009   0.0000 -1.3680 -0.6090
F2      0.4788  0.4788 -0.1991  -0.0000  1.3680 -0.6090
F3      0.4788 -0.5212 -0.1991   1.4790 -0.0606 -0.2262
I      -0.4467 -0.5533 -0.5000   0.1576 -1.4286 -0.2262
I1      0.4467 -0.4467 -0.5000   1.3213  0.0000 -0.6090
L      -0.5000 -0.5000 -0.5000   0.0000 -1.4286 -0.2262
M       0.0000 -0.5000 -0.5000   0.7395 -0.7143 -0.4176
X       0.5000 -0.5000  0.0000   1.4790  0.0000  0.0000
X1     -0.5000 -0.5000 -0.0000   0.0000 -1.4286  0.3828
X2      0.5000  0.5000  0.0000   0.0000  1.4286 -0.3828
Y      -0.5000 -0.5000 -0.0000   0.0000 -1.4286  0.3828
Y1      0.5000  0.5000  0.0000   0.0000  1.4286 -0.3828
Z       0.0000  0.0000 -0.5000   0.0000  0.0000 -0.6090

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)
pe.plot_kpoints(kp=kp, only_from_kpath=True)

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)