principia_materia.translation_group.qpoints_n module

class principia_materia.translation_group.qpoints_n.QpointsN(vec, supa, order, pg='C1', tol=1e-06)

Bases: Lattice

A list of Q-points at a given order that fit in a given supercell find irreducible Q with point and permutaion symmetry.

Parameters:

• vec (array of float, shape(dim, dim)) – The lattice vectors, in row convention.

• supa (array of int, shape(dim, dim)) – Super lattice matrix.

• pg (str or a PointGroup object) – The point group of the lattice.

• tol (float, optional, default to 1.0E-6) – Tolerance threshold.

property Qpoints

The Q-points that fit in the supercell.

property Qpoints_orbits

find_irreducible_Qpoints()

Find the irreducible set of Q-points under the given symmetry.

get_Qindex(Qpoints)

Computes the indices of Q-points.

property irreducible_Qpoints

The irreducible Qpoints.

property irreducible_Qpoints_Qind

The index of the irreducible Q-points in the Q-points list.

property irreducible_Qpoints_inverse

The index of the corresponding irreducible Q-points of the Q-points in the irreducible Q-points list.

property irreducible_Qpoints_map

The corresponding irreducible Q-point index in the irreducible Q-point list for each Q-point.

property irreducible_Qpoints_mult

The multiplicity of the irreducible Q-points.

property irreducible_Qpoints_permutation

The permutation that maps a Q-point to the corresponding irreducible Q-point.

property irreducible_Qpoints_rotation

The point group operation that maps a Q-point to the corresponding irreducible Q-point.

property multiplicity

The multiplicity of the supercell.

property nQpoints

Number of Q-points

property n_irreducible_Qpoints

property supa

The supercell matrix.

to_dict()

Return a dictionary containing key information about the QpointsN object.

class principia_materia.translation_group.qpoints_n.QpointsPerm(vec, supa, order, pg='C1', tol=1e-06)

Bases: Lattice

A list of Q-points at a given order that fit in a given supercell, find permutationally irreducible Q.

For a given order N Q point, in contains N-1 independent q-point, since the Q point needs to satisfy conservation of momentum and the sum of all q-points in a Q point must be equivalent to Gamma point (0, 0, 0).

Parameters:

• vec (array of float, shape(dim, dim)) – The lattice vectors, in row convention.

• supa (array of int, shape(dim, dim)) – Super lattice matrix.

• pg (str or a PointGroup object) – The point group of the lattice.

• tol (float, optional, default to 1.0E-6) – Tolerance threshold.

property Qpoints

The Q-points that fit in the supercell.

find_permutationally_irreducible_Qpoints()

Find the permutationally irreducible set of Q-points.

get_Qindex(Qpoints)

Computes the indices of Q-points.

property irreducible_Qpoints

The irreducible Q-points.

property irreducible_Qpoints_Qind

The index of the irreducible Q-points in the Q-points list.

property irreducible_Qpoints_inverse

The index of the corresponding irreducible Q-points of the Q-points in the irreducible Q-points list.

property irreducible_Qpoints_map

The index of corresponding irreducible Q-point of each Q-point.

property irreducible_Qpoints_mult

The multiplicity of each irreducible Q-point.

property irreducible_Qpoints_permutation

The permutation that transform the Q-point to the corresponding irreducible Q-point.

property multiplicity

The multiplicity of the supercell.

property nQpoints

Number of Q-points.

property n_irreducible_Qpoints

Number of irreducible Q-points.

property supa

The supercell matrix.

to_dict()

Return a dictionary containing key information about the QpointsPerm object.

principia_materia.translation_group.qpoints_n.get_QpointsN_io_wrapper(title='QpointsN')

YAML data wrapper for QpointsN class.