pyspinw.anisotropy#

Different kinds of anisotropy.

Functions

specialise_anisotropy(anisotropy)

Find the narrowest anisotropy subclass to fit the exchange

Classes

Anisotropy(site, anisotropy_matrix[, name])

Represent the anisotropy term at a given site.

AxisMagnitudeAnisotropy(site, a[, ...])

Represent a uniaxial anisotropy term.
class pyspinw.anisotropy.Anisotropy(site: Site, anisotropy_matrix: ArrayLike, name: str = '')#

Bases: SPWSerialisable

Represent the anisotropy term at a given site.

Parameters:

  • site – Lattice site to which the anisotropy term applies.

  • anisotropy_matrix – 3x3 matrix defining the anisotropy contribution for the site.

  • name – Optional name

property anisotropy_matrix: ndarray#

Matrix specifying the anisotropy - A term in the Hamiltonian.

generalise()#

Returns the most general version of this class

property name#

Name of this anisotropy

obeys_symmetry(structure: Structure)#

Check that this anisotropy is consistent with the symmetry group

property parameter_string#

A string representation of the parameters.

scalar_parameters = []#

Names of scalar fields that can be varied by parameter definitions.

serialisation_name = 'anisotropy'#

Type name used when serialising anisotropy terms to SPW data.

property site#

Get the site for this anisotropy.

specialise()#

Convert this to the most specific anisotropy class possible

symmetry_copy(structure: Structure, site: Site)#

Copy this anisotropy using symmetry operations

symmetry_fill(structure: Structure, include_original=False, specialisation_rounding_exponent: int | None = 14)#

Make multiple copies of this anisotropy so that symmetry is satisfied

property unique_id#

Unique ID for this anisotropy.

updated(site: Site | None = None, anisotropy_matrix: ArrayLike | None = None, name: str = '')#

Return a copy of this anisotropy term with variables replaced.

Parameters:

  • site – Replacement lattice site. If omitted, the current site is reused.

  • anisotropy_matrix – Replacement anisotropy matrix. If omitted, the current matrix is reused.

  • name – Optional name. If omitted, current name is reused.

class pyspinw.anisotropy.AxisMagnitudeAnisotropy(site: Site, a: float, direction: ArrayLike = array([0, 0, 1]), name: str = '')#

Bases: Anisotropy

Represent a uniaxial anisotropy term.

Parameters:

  • site – Lattice site to which the anisotropy term applies.

  • a – Anisotropy constant.

  • direction – Principal anisotropy direction. The vector is normalized before use.

  • name – Optional name.

property a#

Amount of anisotropy (anisotropy constant).

property constant#

Amount of anisotropy (anisotropy constant), alias for a.

property direction#

The principal direction of the anisotropy.

property parameter_string#

A string representation of the parameters.

scalar_parameters = ['a']#

Names of scalar fields that can be varied by parameter definitions.

updated(site: Site | None = None, a: float | None = None, direction: ArrayLike | None = None, name: str | None = None)#

Return a copy of this anisotropy term with variables replaced.

Parameters:

  • site – Replacement lattice site. If omitted, the current site is reused.

  • a – Replacement anisotropy constant. If omitted, the current constant is reused.

  • direction – Replacement principal anisotropy direction. If omitted, the current direction is reused.

  • name – Optional name. If omitted, current name is reused.

pyspinw.anisotropy.specialise_anisotropy(anisotropy: Anisotropy) → Anisotropy#

Find the narrowest anisotropy subclass to fit the exchange