Properties Data

We make use of the data convention, introduced in this page, to organize the information related to properties.

JSON Schemas and Examples

We provide below an example of a JSON schema for a material property. The reader is referred to the JSON external documentation 1 2 for the explanation of the primitive types and schema keywords.

Also listed below, is an example of a JSON representation of the total energy, which can validated by the schema. It consists in a scalar numerical value, which is expressed in units of electronVolts (eV).

Data Convention 
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{
    "schemaId": "properties-directory/scalar/total-energy",
    "$schema": "http://json-schema.org/draft-04/schema#",
    "title": "total energy schema",
    "allOf": [
        {
            "schemaId": "core/reusable/energy",
            "title": "energy schema",
            "allOf": [
                {
                    "schemaId": "core/primitive/scalar",
                    "title": "scalar schema",
                    "type": "object",
                    "properties": {
                        "value": {
                            "type": "number"
                        }
                    },
                    "required": [
                        "value"
                    ]
                }
            ],
            "properties": {
                "name": {
                    "type": "string"
                },
                "units": {
                    "anyOf": [
                        {
                            "enum": [
                                "kJ/mol",
                                "eV",
                                "J/mol",
                                "hartree",
                                "cm-1",
                                "rydberg",
                                "eV/atom"
                            ]
                        },
                        {
                            "enum": [
                                "eV/A^2"
                            ]
                        }
                    ]
                }
            },
            "required": [
                "name",
                "units"
            ]
        }
    ],
    "properties": {
        "name": {
            "enum": [
                "total_energy"
            ]
        }
    }
}

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{
    "name": "total_energy",
    "units": "eV",
    "value": -123.43573079
}

Core Schema Types

In addition to the default primitive types for JSON Schemas, we construct additional types used for constructing the representations of properties. A list of available schema types are provided in this page.

List of Schemas

In this section, we offer a full list of schemas and examples relevant for properties. The properties relevant for each element in the Periodic Table are also listed separately.

  1. JSON Schema Core Documentation, Website ↩

  2. JSON Schema Validation Documentation, Website ↩