wulfric.Kpoints.from_crystal#

method

static Kpoints.from_crystal(cell, atoms, convention='HPKOT', with_time_reversal=True, n=100, spglib_data=None)[source]#
Parameters:
cell(3, 3) array-like

Matrix of a cell, rows are interpreted as vectors.

atomsdict

Dictionary with N atoms. Expected keys:

  • "positions" : (N, 3) array-like

    Positions of the atoms in the basis of lattice vectors (cell). In other words - relative coordinates of atoms.

  • "names" : (N, ) list of str, optional

    See Notes

  • "species" : (N, ) list of str, optional

    See Notes

  • "spglib_types" : (N, ) list of int, optional

    See Notes

Hint

Pass atoms = dict(positions=[[0, 0, 0]], spglib_types=[1]) if you would like to interpret the cell alone (effectively assuming that the cell is a primitive one).

conventionstr, default "HPKOT"

Convention for the definition of the conventional cell. Case-insensitive. Supported:

with_time_reversalbool, default True

Whether to assume that the system has time reversal symmetry. By default assumes that the system has it. The strategy for extending the path when with_time_reversal=False for the crystals without inversion symmetry is described in [1]. For the systems with inversion symmetry this parameter does nothing.

Added in version 0.6.3.

nint, default 100

Number of intermediate points between each pair of the high-symmetry points (high-symmetry points excluded).

spglib_dataSyntacticSugar, optional

If you need more control on the parameters passed to the spglib, then you can get spglib_data manually and pass it to this function. Use wulfric's interface to spglib as

spglib_data = wulfric.get_spglib_data(...)

using the same cell and atoms["positions"] that you are passing to this function.

Notes

spglib uses types to distinguish the atoms. To see how wulfric deduces the types for given atoms see wulfric.get_spglib_types().

If two atoms i and j have the same spglib_type (i.e. atoms["spglib_types"][i] == atoms["spglib_types"][j]), but they have different property that is stored in atoms[key] (i.e atoms[key][i] != atoms[key][j]), then those two atoms are considered equal. In the returned conventional_atoms the value of the conventional_atoms[key] are populated based on the last found atom in atoms with each for spglib_type. This rule do not apply to the "positions" key.

References

[1] (1,2)

Hinuma, Y., Pizzi, G., Kumagai, Y., Oba, F. and Tanaka, I., 2017. Band structure diagram paths based on crystallography. Computational Materials Science, 128, pp.140-184.

[2]

Setyawan, W. and Curtarolo, S., 2010. High-throughput electronic band structure calculations: Challenges and tools. Computational materials science, 49(2), pp. 299-312.