This page documents an OPTIMADE Property Definition. See https://schemas.optimade.org/ for more information.
ID: https://schemas.optimade.org/defs/v1.3/properties/optimade/trajectories/site_coordinate_span_description
Definition name: site_coordinate_span_description
Property name: list of site coordinate span description
Description: A list of site_coordinate_span_description items.
A site_coordinate_span_description item is a human-readable semi-formal characterization of the coordinate span when the site_coordinate_span property has value other.
Type: list
Examples:
["Two fullerene molecules with a VdW contact.", "One fullerene molecule"]JSON definition:
{
"$id": "https://schemas.optimade.org/defs/v1.3/properties/optimade/trajectories/site_coordinate_span_description",
"$schema": "https://schemas.optimade.org/meta/v1.3/optimade/property_definition.json",
"title": "list of site coordinate span description",
"x-optimade-type": "list",
"x-optimade-definition": {
"label": "site_coordinate_span_description_optimade_trajectories",
"kind": "property",
"version": "1.3.0",
"format": "1.3",
"name": "site_coordinate_span_description"
},
"x-optimade-dimensions": {
"names": [
"dim_frames"
],
"sizes": [
null
],
"compactable": [
"constant"
]
},
"type": [
"array",
"null"
],
"description": "A list of site_coordinate_span_description items.\nA site_coordinate_span_description item is a human-readable semi-formal characterization of the coordinate span when the `site_coordinate_span` property has value `other`.",
"examples": [
[
"Two fullerene molecules with a VdW contact.",
"One fullerene molecule"
]
],
"x-optimade-unit": "inapplicable",
"items": {
"$id": "https://schemas.optimade.org/defs/v1.3/properties/optimade/structures/site_coordinate_span",
"title": "site coordinate span",
"x-optimade-type": "string",
"x-optimade-definition": {
"label": "site_coordinate_span_optimade_structures",
"kind": "property",
"version": "1.3.0",
"format": "1.2",
"name": "site_coordinate_span"
},
"type": [
"string",
"null"
],
"description": "Indicates the extent of the material (crystal) described in the response.\nIn particular, properties `cartesian_site_positions` and `fractional_site_positions` MUST contain all sites *belonging* to the described extent.\n\nThe value of this property MUST be one of the following:\n\n * `fundamental_domain`: means that sites described in the response span a fundamental domain (Vinberg, 1994; European Mathematical Society, 2020) of a periodic system.\n When a server indicates this span in the response, it MUST provide those sites that enable reconstruction of the whole periodic system by applying symmetry operations from `space_group_symmetry_operations_xyz` property and then applying translations given by `lattice_vectors`.\n The fundamental domain does not need to be a connected space region.\n\n * `asymmetric_unit`: all sites are in a simply connected space region that is a fundamental domain, as per IUCr Online Dictionary of Crystallography definition (IUCr, 2017).\n\n * `molecular_fundamental_domain`: a fundamental domain where all atoms connected by covalent or donor-acceptor coordination bonds are adjacent to each other, placed at a bond distance.\n\n * `molecular_asymmetric_unit`: an asymmetric unit (a simply connected fundamental domain) where all atoms bound by covalent or donor-acceptor coordination bonds are adjacent to each other, placed at a bond distance.\n\n * `unit_cell`: a full unit cell of a periodic system (crystal), i.e., any repeating unit chosen by the server defined by the property `lattice_vectors`.\n For this span, the server MUST provide a set of sites in the response that can be used to reconstruct the whole periodic system (crystal) by simply applying translations from the `lattice_vectors` property to those sites.\n\n * `molecular_unit_cell`: same as `unit_cell`, but in addition places atoms that are bound by covalent or coordination bonds at a bond distance from each other.\n\n * `molecular_entities`: sets of atoms that are bound by covalent or coordination bonds, as per IUPAC definition of a 'molecular entity'.\n This set of sites MAY be larger than a fundamental domain.\n\n * `other`: any other collection of sites that does not fit the enumerated values above.\n\n * `null`: if omitted or `null`, the default value of `site_coordinate_span` is `unit_cell`.\n This is the assumed behavior of all main implementations before the `site_coordinate_span` definition was introduced.\n\n**Note**: In all cases it is RECOMMENDED that only the minimal set of the sites that is needed to reconstruct the whole material is provided.\nFor example, for the 'unit_cell' span the server SHOULD NOT return sites that can be obtained from other returned sites through the translations given in `lattice_vectors`; only a non-redundant set of sites SHOULD be provided.\n\n**Bibliographic References**:\n\nE.B. Vinberg (originator). (1994) Encyclopedia of Mathematics. ISBN `1402006098 <https://isbnsearch.org/isbn/1402006098>`__, URL: https://encyclopediaofmath.org/index.php?title=Fundamental_domain&oldid=13590 [accessed 2025-04-30T08:55+03:00].\n\nEuropean Mathematical Society (2020). Fundamental domain. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Fundamental_domain&oldid=47023 [accessed 2025-04-30T08:53+03:00].\n\nIUCr (2017). Asymmetric unit. Online Dictionary of Crystallography, URL: https://dictionary.iucr.org/Asymmetric_unit [accessed 2025-04-30T09:01+03:00].",
"examples": [
"asymmetric_unit",
"unit_cell"
],
"x-optimade-unit": "inapplicable",
"enum": [
"fundamental_domain",
"asymmetric_unit",
"molecular_fundamental_domain",
"molecular_asymmetric_unit",
"unit_cell",
"molecular_unit_cell",
"molecular_entities",
"other"
]
}
}