httk.atomistic.models.structure.symops
======================================

.. py:module:: httk.atomistic.models.structure.symops

.. autoapi-nested-parse::

   A structure represented by a CIF site's own complete symmetry operations.



Classes
-------

.. autoapisummary::

   httk.atomistic.models.structure.symops.SymopsStructure


Module Contents
---------------

.. py:class:: SymopsStructure(cell, sites, species, species_at_sites, symops, *, site_moments = None, bns_number = None, bns_label = None, chemical_composition = None, chemical_formula_descriptive = None, chemical_formula_hill = None, optimization_type = None, immutable_id = None, last_modified = None, charge = None)

   Bases: :py:obj:`httk.atomistic.models.structure.semantics.StructureSemanticsMixin`, :py:obj:`httk.atomistic.models.structure.backend.StructureBackend`


   Represent a magCIF cell, listed sites, and its complete symmetry-operation list.

   The operations are taken as declared. They are not checked for group closure: magCIF
   lists complete coset representatives, and an incomplete list consequently under-expands.
   Expansion is exact and deduplicates only by normalized fractional coordinates, species,
   and exact transformed moments.

   :param cell: The cell geometry.
   :param sites: The listed site coordinates.
   :param species: The distinct species definitions.
   :param species_at_sites: The species name occupying each listed site.
   :param symops: The declared spatial or magnetic symmetry operations.
   :param site_moments: Optional moments aligned with the listed sites.
   :param bns_number: Optional Belov–Neronova–Smirnova number.
   :param bns_label: Optional Belov–Neronova–Smirnova label.
   :param chemical_composition: Optional chemical composition metadata.
   :param chemical_formula_descriptive: Optional descriptive chemical formula.
   :param chemical_formula_hill: Optional Hill chemical formula.
   :param optimization_type: Optional optimization provenance.
   :param immutable_id: Optional immutable source identifier.
   :param last_modified: Optional source modification timestamp.
   :param charge: An explicitly assigned charge for the cell content.
   :raises TypeError: If an input component or magnetic label has the wrong kind.
   :raises ValueError: If component lengths, operations, or semantic values are invalid.


   .. py:attribute:: kind
      :type:  ClassVar[str]
      :value: 'symops'



   .. py:property:: cell
      :type: httk.atomistic.models.cell.cell.Cell


      Expose the cell geometry.

      :return: The exact cell.


   .. py:property:: listed_sites
      :type: httk.atomistic.models.sites.sites.Sites


      Expose the sites before symmetry expansion.

      :return: The listed site coordinates.


   .. py:property:: listed_species_at_sites
      :type: tuple[str, Ellipsis]


      Expose species names before symmetry expansion.

      :return: Listed site species names in input order.


   .. py:property:: listed_site_moments
      :type: httk.atomistic.models.moments.backend.SiteMomentsBackend | None


      Expose moments before symmetry expansion.

      :return: Listed site moments, or ``None`` when unstated.


   .. py:property:: symops
      :type: tuple[tuple[httk.atomistic.symmetry.affine_operation.AffineOperation, int], Ellipsis]


      Expose normalized spatial and time-reversal operations.

      :return: Operation and time-reversal pairs in declaration order.


   .. py:property:: bns_number
      :type: str | None


      Expose the Belov–Neronova–Smirnova number.

      :return: The BNS number, or ``None`` when unstated.


   .. py:property:: bns_label
      :type: str | None


      Expose the Belov–Neronova–Smirnova label.

      :return: The BNS label, or ``None`` when unstated.


   .. py:property:: species
      :type: tuple[httk.atomistic.models.species.species.Species, Ellipsis]


      Expose the distinct species.

      :return: Species referenced by the listed sites.


   .. py:property:: coordinate_precision
      :type: Any


      Expose the listed-coordinate precision.

      :return: The fractional coordinate precision.


   .. py:property:: basis_precision
      :type: Any


      Expose the cell-basis precision.

      :return: The basis precision.


   .. py:property:: periodicity
      :type: tuple[bool, bool, bool]


      Expose the cell periodicity flags.

      :return: Periodicity flags for the three cell directions.


   .. py:property:: molecular
      :type: bool


      Expose whether the structure is molecular.

      :return: Always ``False`` for this backend.


   .. py:property:: site_coordinate_span
      :type: str


      Expose the coordinate span of the listed sites.

      :return: ``"unit_cell"``.


   .. py:property:: charge
      :type: fractions.Fraction | None


      Expose the explicitly assigned charge.

      :return: The charge, or ``None`` when unstated.


   .. py:method:: cartesian_sites()

      Compute exact Cartesian positions for the expanded sites.

      :return: Cartesian positions in the exact surd representation.



   .. py:property:: sites
      :type: httk.atomistic.models.sites.sites.Sites


      Expose the symmetry-expanded sites.

      :return: Expanded site coordinates.


   .. py:property:: species_at_sites
      :type: tuple[str, Ellipsis]


      Expose species names for the expanded sites.

      :return: Expanded site species names in site order.


   .. py:property:: site_moments
      :type: httk.atomistic.models.moments.backend.SiteMomentsBackend | None


      Expose moments transformed onto the expanded sites.

      :return: Expanded site moments, or ``None`` when moments were unstated.