httk property definitionsProperty definitions using the OPTIMADE property definition format, hosted by httk
v0.1
datasets
Point groups (property) - https://schemas.httk.org/defs/v0.1/datasets/pointgroups
Ordered table of crystallographic point-group records. Each item contains point-group classification, finite point-group operations, conjugacy classes, and real and complex character tables generated from cctbx and spgrep.
Space groups (property) - https://schemas.httk.org/defs/v0.1/datasets/spacegroups
Ordered table of crystallographic space-group setting records.
Each item describes one concrete Hall/International Tables setting of a space group, including symbols, classifications, symmetry operations, asymmetric-unit information, Wyckoff positions, and related auxiliary data.
The companion top-level indicies.index_hall_entry_to_spacegroups lookup maps normalized Hall entries to indices in this list; it is not an OPTIMADE property.
Transformations (property) - https://schemas.httk.org/defs/v0.1/datasets/transformations
Ordered table of crystallographic transformation records.
Each item describes transformations and normalizer information for one concrete International Tables H-M entry.
In transformations_hm_entry.json.gz, items are keyed for lookup by the companion top-level indicies.index_hm_entry_to_transformations_per_hm_entry object; that index is not an OPTIMADE property.
entrytypes
httk point group symmetry fields (entrytype) - https://schemas.httk.org/defs/v0.1/entrytypes/pointgroups
httk records entry type (entrytype) - https://schemas.httk.org/defs/v0.1/entrytypes/records
A records entry carries the value of one formally declared property (a computed or measured quantity) as its own entry, so that multiple parallel determinations of the same quantity for the same system can coexist as separate entries linked via provenance relationships. The value properties served on this entry type are declared per provider through property definitions and are not enumerated here.
httk runs entry type (entrytype) - https://schemas.httk.org/defs/v0.1/entrytypes/runs
A runs entry represents one specific, individual execution of a workflow or process that consumed and/or produced other entries. Provenance edges (inputs, artifacts, outputs) are expressed as relationships, not properties.
httk space group symmetry fields (entrytype) - https://schemas.httk.org/defs/v0.1/entrytypes/spacegroups
httk transformation fields (entrytype) - https://schemas.httk.org/defs/v0.1/entrytypes/transformations
properties
chemistry
Species constituent charges (property) - https://schemas.httk.org/defs/v0.1/properties/chemistry/species_charges
The explicitly assigned charge of each constituent of a species, as a dimensionless charge number, i.e., the charge in units of the elementary charge.
Species constituent labels (property) - https://schemas.httk.org/defs/v0.1/properties/chemistry/species_labels
A free-form label attached to each constituent of a species.
Species constituent spins (property) - https://schemas.httk.org/defs/v0.1/properties/chemistry/species_spins
The idealized spin assigned to each constituent of a species, as a dimensionless signed number.
Structure charge (property) - https://schemas.httk.org/defs/v0.1/properties/chemistry/structure_charge
The explicitly assigned net charge of the whole structure, as a dimensionless charge number, i.e., the charge in units of the elementary charge.
core
Fraction (property) - https://schemas.httk.org/defs/v0.1/properties/core/fraction
A numerical representation formed as the quotient of two numbers represented as a string.
Fractional coordinate precision (property) - https://schemas.httk.org/defs/v0.1/properties/core/fractional_coordinate_precision
The absolute precision of a set of fractional coordinates, in fractional units.
Length precision (property) - https://schemas.httk.org/defs/v0.1/properties/core/length_precision
The absolute precision of a stated length, in ångström.
source ID (property) - https://schemas.httk.org/defs/v0.1/properties/core/source_id
The run's identifier in the system that executed it. For httk-workflow jobs, this is the workspace and job identity in the form
String markups (property) - https://schemas.httk.org/defs/v0.1/properties/core/string_markups
Strings with alternate markup and/or encoding for display rendering.
Total energy (property) - https://schemas.httk.org/defs/v0.1/properties/core/total_energy
The total energy of a computed system as produced by a calculation, in electronvolt. The reference/zero of the total energy scale is method- and code-specific, so values are comparable only within one consistent computational setup.
Workflow declaration URI (property) - https://schemas.httk.org/defs/v0.1/properties/core/workflow_declaration_uri
A URI identifying the workflow declaration (the reusable process definition, as opposed to a specific execution) behind a runs entry. No particular URI scheme, resolvability, or formalism is mandated. Providers wanting two runs recognized as executions of the same declaration MUST use an identical URI. Null is expected for ad-hoc scripts, interactive executions, and legacy data with no formal workflow identifier.
electronic
DFT band gap (property) - https://schemas.httk.org/defs/v0.1/properties/electronic/dft_band_gap
The Kohn-Sham band gap of a material from a density-functional-theory (DFT) calculation, given in electronvolts. Its value depends on the computational method and exchange-correlation functional used.
magnetism
MAGNDATA identifiers (property) - https://schemas.httk.org/defs/v0.1/properties/magnetism/magndata_ids
The identifiers of MAGNDATA magnetic-structure entries associated with a material.
Magnetic space group (BNS) (property) - https://schemas.httk.org/defs/v0.1/properties/magnetism/magnetic_space_group_bns
The magnetic space group of a material in Belov-Neronova-Smirnova (BNS) notation.
Site magnetic moments (property) - https://schemas.httk.org/defs/v0.1/properties/magnetism/site_moments
The magnetic moment vector of each site, in Cartesian coordinates and Bohr magnetons.
pointgroups
Complex character table (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/character_table_complex
Complex irreducible character table of the crystallographic point group.
Real character table (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/character_table_real
Real irreducible character table of the crystallographic point group.
Conjugacy classes (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/conjugacy_classes
Conjugacy classes of a crystallographic point group.
Crystal system (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/crystal_system
The crystal system of the space group or point group.
Hermann-Mauguin symbol (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/hm_symbol
Hermann-Mauguin point-group symbol used as the key and display symbol for a point-group record.
is centrosymmetric (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/is_centrosymmetric
Boolean flag indicating whether the point group contains inversion symmetry.
Laue class (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/laue_class
The Laue class associated with the space group or point group.
Number of conjugacy classes (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/n_conjugacy_classes
Number of conjugacy classes in the crystallographic point group.
Number of point-group operations (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/n_pointgroup_symops
Number of point-group symmetry operations.
Order of the point group (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/order
Order of the point group, i.e. the number of operations in the finite point group.
Schoenflies symbol (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/schoenflies
The Schoenflies symbol for the crystallographic point group.
Schoenflies symbol markups (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/schoenflies_markup
Display-oriented renderings of the Schoenflies symbol in schoenflies.
The plain string value is stored in the corresponding unsuffixed property; this object only provides alternate markup forms for display.
Symmetry operations (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/symops
Full list of symmetry-operation descriptors for a point group.
Each list member is an op object as defined by /defs/v0.1/properties/symmetry/op.
Point-group operations have a zero translation part, so the screw_glide and origin_shift classification fields are omitted.
spacegroups
Asymmetric unit (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/asu
Direct-space asymmetric unit for the space-group setting, represented as a bounded non-recursive set of half-space cuts and boundary ownership rules.
Asymmetric-unit cut (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/asu_cut
One serialized asymmetric-unit half-space cut or logical cut expression in the recursive cctbx source representation.
Asymmetric unit markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/asu_markup
Display-oriented renderings of the plain-string asymmetric-unit restrictions in asu_str.
Shape-only asymmetric unit markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/asu_shape_only_markup
Display-oriented renderings of the plain-string shape-only asymmetric-unit restrictions in asu_shape_only_str.
Shape-only asymmetric unit string (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/asu_shape_only_str
Plain string rendering of the geometric shape part of the asymmetric-unit restrictions, without conditional refinements.
Asymmetric unit string (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/asu_str
Plain string rendering of the asymmetric-unit restrictions for the space-group setting.
Bravais type (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/bravais_type
The Bravais type of the translational lattice.
cctbx FFT grid factors (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/cctbx_fft_grid_factors
FFT grid-factor requirements derived from cctbx for the space group, its structure seminvariants, and its Euclidean normalizer.
Centering translations (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/centering_translations
Centering translations of the conventional cell.
Centring type (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/centring_type
The lattice centring symbol for the crystallographic setting.
Crystal system (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/crystal_system
The crystal system of the space group or point group.
Hall symbol (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hall
The Hall symbol for a crystallographic space-group setting.
Hall symbol aliases (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hall_aliases
Alternate ASCII Hall symbols or Hall-setting keys associated with the same generated setting.
Hall alias markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hall_aliases_markup
Display-oriented renderings corresponding element-by-element to the alternate Hall symbols in hall_aliases.
Hall entry (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hall_entry
Normalized Hall-table entry key used internally by the generated datasets.
Hall symbol markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hall_markup
Display-oriented renderings of the Hall symbol in hall.
Harker planes (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/harker_planes
Harker planes of the space group in fractional Patterson coordinates.
Universal cctbx Hermann-Mauguin symbol (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_cctbx_universal
Universal Hermann-Mauguin symbol returned by cctbx for this setting.
Hermann-Mauguin entry (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_entry
The Hermann-Mauguin entry label for a conventional space-group setting from table A1.4.2.7 of the International Tables for Crystallography (2006). Volume B, Reciprocal space. ISBN: 978-0-7923-6592-1, doi:10.1107/97809553602060000102.
Hermann-Mauguin entry aliases (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_entry_aliases
Alternative Hermann-Mauguin entry labels from International Tables for Crystallography Volume B table A1.4.2.7 that identify the same generated Hall-symbol row as hm_entry.
Hermann-Mauguin entry markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_entry_markup
Display-oriented renderings of the Hermann-Mauguin entry label in hm_entry.
Extended Hermann-Mauguin symbol (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_extended
The setting-specific extended Hermann-Mauguin symbol for the space-group setting.
Extended Hermann-Mauguin symbol aliases (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_extended_aliases
Alternate ASCII forms of hm_extended that are accepted for the same generated setting.
Extended Hermann-Mauguin alias markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_extended_aliases_markup
Display-oriented renderings corresponding element-by-element to the alternate extended Hermann-Mauguin symbols in hm_extended_aliases.
Extended Hermann-Mauguin symbol markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_extended_markup
Display-oriented renderings of the extended Hermann-Mauguin symbol in hm_extended.
Extended Hermann-Mauguin symbol in old notation (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_extended_old
The older extended Hermann-Mauguin symbol retained as an alias for symbols superseded by newer e-glide notation.
Full Hermann-Mauguin symbol (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_full
The setting-specific full Hermann-Mauguin symbol for the space-group setting.
Full Hermann-Mauguin symbol aliases (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_full_aliases
Alternate ASCII forms of hm_full that are accepted for the same generated setting.
Full Hermann-Mauguin alias markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_full_aliases_markup
Display-oriented renderings corresponding element-by-element to the alternate full Hermann-Mauguin symbols in hm_full_aliases.
Full Hermann-Mauguin symbol markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_full_markup
Display-oriented renderings of the setting-specific full Hermann-Mauguin symbol in hm_full.
Full Hermann-Mauguin symbol in old notation (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_full_old
The older full Hermann-Mauguin symbol retained as an alias for symbols superseded by newer e-glide notation.
Standard full Hermann-Mauguin symbol (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_full_std
The International Tables standard full Hermann-Mauguin symbol for the space-group type.
Standard full Hermann-Mauguin symbol markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_full_std_markup
Display-oriented renderings of the ITA-standard full Hermann-Mauguin symbol in hm_full_std.
Short Hermann-Mauguin symbol (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_short
The setting-specific short Hermann-Mauguin symbol for the space-group setting.
Short Hermann-Mauguin symbol aliases (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_short_aliases
Alternate ASCII forms of hm_short that are accepted for the same generated setting.
Short Hermann-Mauguin alias markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_short_aliases_markup
Display-oriented renderings corresponding element-by-element to the alternate short Hermann-Mauguin symbols in hm_short_aliases.
Short Hermann-Mauguin symbol markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_short_markup
Display-oriented renderings of the setting-specific short Hermann-Mauguin symbol in hm_short.
Short Hermann-Mauguin symbol in old notation (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_short_old
The older short Hermann-Mauguin symbol retained as an alias for symbols superseded by newer e-glide notation.
Standard short Hermann-Mauguin symbol (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_short_std
The International Tables standard short Hermann-Mauguin symbol for the space-group type.
Standard short Hermann-Mauguin symbol markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/hm_short_std_markup
Display-oriented renderings of the ITA-standard short Hermann-Mauguin symbol in hm_short_std.
is centric (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/is_centric
Whether the space group contains an inversion operation (W,w) with W = -I.
The inversion center need not be the coordinate origin; one such center is at w/2 in fractional coordinates.
This tests the space-group symmetry, not the centricity of an individual diffraction reflection.
is chiral (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/is_chiral
Whether every operation of the space group preserves handedness, i.e. every linear part has determinant +1.
This is cctbx's is_chiral() convention and identifies the 65 Sohncke space-group types, excluding mirrors, inversion, glide reflections, and rotoinversions.
It does not mean that the space-group type belongs to one of the 11 enantiomorphic pairs; that is recorded by is_enantiomorphic.
It does not by itself determine the handedness or chirality of a molecular motif.
is enantiomorphic (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/is_enantiomorphic
Boolean flag indicating whether the space-group type belongs to an enantiomorphic pair.
is reference setting (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/is_reference_setting
Whether cctbx identifies this Hall setting as its reference setting for the space-group type.
This is the reference used by cctbx's change-of-basis machinery; it must not be inferred solely from the setting-specific Hermann-Mauguin symbol.
For the pipeline's selected IT-standard setting, use index_it_number_to_std_spacegroups in the dataset's companion indicies structure.
International Tables coordinate-system code (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/it_coordinate_system_code
The International Tables coordinate-system code for the setting.
International Tables space-group number (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/it_number
The International Tables space-group number.
International Tables number of the enantiomorph (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/it_number_enantiomorphic
International Tables number of the enantiomorphic partner space group, when one exists.
Laue class (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/laue_class
The Laue class associated with the space group or point group.
Number of centering translations (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/n_centering_translations
Number of centering translations in the conventional cell of the space-group setting.
Number of point-group operations (property) - https://schemas.httk.org/defs/v0.1/properties/pointgroups/n_pointgroup_symops
Number of point-group symmetry operations.
Number of symops (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/n_symops
Number of symmetry operations in the finite operation list of the generated entry.
Point-group Hermann-Mauguin symbol (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/point_group
The Hermann-Mauguin point-group symbol for the crystallographic point group of the space group.
Schoenflies symbol (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/schoenflies
The Schoenflies symbol for the space-group type.
Schoenflies symbol markups (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/schoenflies_markup
Display-oriented renderings of the space-group Schoenflies symbol in schoenflies.
The plain string value is stored in the corresponding unsuffixed property; this object only provides alternate markup forms for display.
Setting annotation (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/setting
Setting suffix or setting annotation extracted from the cctbx universal Hermann-Mauguin symbol in hm_cctbx_universal.
International Tables setting code n:c (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/setting_it_nc
International Tables setting identifier in n:c notation.
International Tables setting-code aliases (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/setting_it_nc_aliases
A list of International Tables n:c setting identifiers that are alternatives to the one designated as the main one.
Setting plaintext (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/setting_plaintext
Human-readable description of the International Tables coordinate-system setting.
Space-group symbols (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/spacegroup_symbols
Ordered table of conventional space-group symbol rows.
Spglib Hall symbol (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/spglib_hall
The Hall symbol for this setting as spelled by the spglib library.
Spglib Hall numbers (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/spglib_hall_numbers
The spglib Hall numbers corresponding to this Hall setting.
Structure seminvariants (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/structure_seminvariants
Structure-seminvariant vectors and moduli for the space-group setting, describing allowed changes of origin that preserve its symmetry description.
Symmetry operations (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/symops
Full list of symmetry-operation descriptors for a space-group setting.
Symmetry operation generators (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/symops_generators
Generator subset of the finite symmetry-operation list for a space-group setting.
Composition of these operations, with translations reduced modulo integer cell translations, generates symops, including the centering translations.
Integer cell translations are implicit generators of the infinite space group.
The generator selects operations greedily; the list is not promised to have the smallest possible cardinality.
Identity is omitted, so the P1 list is empty.
Symmetry operations modulo centering translations (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/symops_mod_centering
Representative symmetry-operation descriptors modulo centering translations.
Representative symmetry operations (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/symops_representative
Representative symmetry-operation descriptors modulo centering translations: one full-group operation (including inversion-related operations where present) per coset of the centring translations.
Wyckoff positions (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/wyckoff
Wyckoff-position table for a specific space-group setting.
Wyckoff sets (property) - https://schemas.httk.org/defs/v0.1/properties/spacegroups/wyckoff_sets
Sets of Wyckoff letters related by normalizer operations.
symmetry
Affine transformation (property) - https://schemas.httk.org/defs/v0.1/properties/symmetry/affine_transformation
An affine transformation acting on fractional crystallographic coordinates.
Basis transformation (property) - https://schemas.httk.org/defs/v0.1/properties/symmetry/basis_transform
One crystallographic transform between coordinate descriptions, settings, cells, or related group embeddings.
Centering translation (property) - https://schemas.httk.org/defs/v0.1/properties/symmetry/centering_translation
One centering translation of a conventional crystallographic cell.
Operation (property) - https://schemas.httk.org/defs/v0.1/properties/symmetry/op
Information related to a crystallographic operation acting within one coordinate setting.
Operation xyz (property) - https://schemas.httk.org/defs/v0.1/properties/symmetry/op_xyz
Coordinate operation expressed in the algebraic xyz form, also known as Jones' faithful representation (Bradley & Cracknell, 1972: pp. 35-37; adapted for computer strings).
Wyckoff position (property) - https://schemas.httk.org/defs/v0.1/properties/symmetry/wyckoff_position
Information related to a Wyckoff position in a space-group setting.
trajectories
Frame stresses (property) - https://schemas.httk.org/defs/v0.1/properties/trajectories/frame_stresses
The stress tensor of each frame of a trajectory, aligned with the trajectory frame axis (dim_frames).
Each tensor is given in Voigt order [xx, yy, zz, yz, xz, xy], with tensile stress positive, in gigapascal (GPa; 1 GPa = 10^9 Pa).
A null value indicates that the stress tensor of the corresponding frame is unknown.
Frame temperatures (property) - https://schemas.httk.org/defs/v0.1/properties/trajectories/frame_temperatures
The instantaneous temperature of each frame of a trajectory, in kelvin, aligned with the trajectory frame axis (dim_frames).
A null value indicates that the temperature of the corresponding frame is unknown.
Frame total energies (property) - https://schemas.httk.org/defs/v0.1/properties/trajectories/frame_total_energies
The total energy of each frame of a trajectory, in electronvolt, aligned with the trajectory frame axis (dim_frames).
A null value indicates that the energy of the corresponding frame is unknown.
The reference/zero of the total energy scale is method- and code-specific, so values are comparable only within one consistent computational setup.
Time step (property) - https://schemas.httk.org/defs/v0.1/properties/trajectories/time_step
The molecular-dynamics integration time step between consecutive frames, in femtosecond (fs; 1 fs = 10^-15 s).
A null value indicates that the time step is unknown.
transformations
Affine images (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/affine_images
Same-space-group affine images for a standard setting.
Affine normalizer (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/affine_normalizer
Affine normalizer coset representatives for one crystallographic space-group setting.
Affine normalizer coset data (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/affine_normalizer_coset_data
Ordered table of bounded affine normalizer coset-representative data for crystallographic space groups, with one item for each Hall setting.
Affine normalizer cosets (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/affine_normalizer_cosets
Runtime list of bounded affine normalizer coset representatives modulo the space group.
Backward lift criteria (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/backward_lift_criteria
Criteria table for one supergroup IT number used to lift occupied Wyckoff data from a subgroup back to that supergroup along a chosen Bärnighausen transform.
Bärnighausen subgroup transforms (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/baernighausen
Bärnighausen subgroup transform table for one parent setting or space-group type.
Continuous normalizer (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/continuous_normalizer
Parameterized continuous normalizer subspace for a setting.
Euclidean normalizer (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/euclidean_normalizer
Finite Euclidean normalizer operations for one crystallographic space-group setting.
Hall to IT standard transform (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/hall_to_it_std_transform
Exact basis and origin transform from one stored Hall setting to the International Tables standard Hall setting of the same space-group type.
Subgroup or transform index (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/index
Subgroup or transform index.
Isomorphic subgroup transforms (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/isomorphic_subgroups
Isomorphic subgroup transforms of bounded index for one parent setting or space-group type.
Klassengleiche subgroup subtype (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/k_subtype
Subtype of a klassengleiche (k) subgroup relation.
Maximal subgroup relations (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/maximal_subgroup_relations
Maximal non-isomorphic subgroup relations for International Tables space-group types.
Number of coset representatives (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/n_coset_representatives
Number of nontrivial coset representatives retained after deduplication modulo the space group.
Number of cosets (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/n_cosets
Number of affine normalizer coset representatives stored for the setting.
Number of linear parts (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/n_linear_parts
Number of distinct linear matrix parts represented in a normalizer or transform table.
Number of orthogonal cosets (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/n_orthogonal_cosets
Number of orthogonal affine normalizer coset representatives stored for the setting.
Number of raw candidates (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/n_raw_candidates
Number of accepted affine normalizer candidates generated before quotienting modulo the space group and before metric filtering. This is not the number of all linear matrices tested: candidates whose affine normalization equations have no solution are not counted.
Number of unique candidates (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/n_unique_candidates
Number of candidate affine operations remaining after exact duplicate removal.
Orthogonal affine normalizer (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/orthogonal_affine_normalizer
Orthogonal affine normalizer coset representatives for one crystallographic space-group setting.
Orthogonal affine normalizer cosets (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/orthogonal_affine_normalizer_cosets
Runtime list of orthogonal signed-permutation affine normalizer coset representatives modulo the space group.
Same-space-group affine images in the standard setting (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/same_space_group_affine_images_std
Same-space-group affine-image record for one International Tables standard setting.
Maximal subgroup type (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/subgroup_type
International Tables maximal subgroup class.
Criterion target (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/target
Exact right-hand side of a generated modular linear criterion, stored as a list of fraction strings.
To Hall entry (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/to_hall_entry
Target Hall-entry key to which a setting transform maps the current Hall setting.
Transformations per H-M entry (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/transformations_per_hm_entry
Transformation data grouped by H-M entry.
Transformations per IT number (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/transformations_per_it_number
Standard-setting transformation data grouped by International Tables space-group number.
Wyckoff splitting (property) - https://schemas.httk.org/defs/v0.1/properties/transformations/wyckoff_splitting
Wyckoff-position splitting data associated with a subgroup or same-space-group transform.
standards
httk definition provider standard (standard) - https://schemas.httk.org/defs/v0.1/standards/httk
The httk definition provider standard, comprising the spacegroups, pointgroups, and transformations entry types for crystallographic symmetry data.
units
general
femtosecond (unit) - https://schemas.httk.org/defs/v0.1/units/si/general/femtosecond
A unit of time equal to 10^-15 seconds.
gigapascal (unit) - https://schemas.httk.org/defs/v0.1/units/si/general/gigapascal
A unit of pressure and stress equal to 10^9 pascals.
workflows
VASP structure relaxation ([unknown]) - https://schemas.httk.org/defs/v0.1/workflows/vasp-relax
This workflow declaration defines the httk vasp-relax workflow: it relaxes the geometry of a crystal structure with VASP. It defines the meaning of its roles: input role initial_structure is a structures entry containing the structure to relax. Output role relaxed_structure is a structures entry containing the relaxed geometry, and output role total_energy is a records entry containing the final total energy of the relaxed structure.
VASP relaxation and static calculation ([unknown]) - https://schemas.httk.org/defs/v0.1/workflows/vasp-relax-static
This workflow declaration defines the httk vasp-relax-static workflow: it relaxes the geometry, then evaluates the relaxed structure with a final static calculation. It defines the meaning of its roles: input role initial_structure is a structures entry containing the structure to relax. Output role relaxed_structure is a structures entry containing the relaxed geometry, and output role total_energy is a records entry containing the total energy of the relaxed structure from the final static calculation.
VASP static calculation ([unknown]) - https://schemas.httk.org/defs/v0.1/workflows/vasp-static
This workflow declaration defines the httk vasp-static workflow: it performs a single-point total-energy evaluation of a fixed structure with VASP. It defines the meaning of its roles: input role initial_structure is a structures entry containing the structure to evaluate. Output role total_energy is a records entry containing the total energy of the structure.