httk
httk property definitionsProperty definitions using the OPTIMADE property definition format, hosted by httk
Note: prerelease version v0.1, subject to change

Heat capacity at constant volume (property)

This page documents an OPTIMADE Property Definition. See https://schemas.optimade.org/ for more information.

ID: https://schemas.httk.org/defs/v0.1/properties/thermodynamics/heat_capacity_constant_volume
Definition name: heat_capacity_constant_volume

Property name: Heat capacity at constant volume
Description: The heat capacity at constant volume C_V, in electronvolt per kelvin (eV K^-1). Extensive quantity of the whole simulated cell. It may be obtained, e.g., from canonical-ensemble energy fluctuations as Var(E) / (kB T^2), at the temperature recorded alongside. A null value means the quantity is not available or not recorded.
Type: float
Implementation requirements:
- Support: OPTIONAL support in implementations, i.e., MAY be null.

Examples:

Formats: [JSON] [MD]

JSON definition:

{
    "$id": "https://schemas.httk.org/defs/v0.1/properties/thermodynamics/heat_capacity_constant_volume",
    "$schema": "https://schemas.optimade.org/meta/v1.3/optimade/property_definition.json",
    "title": "Heat capacity at constant volume",
    "x-optimade-type": "float",
    "x-optimade-definition": {
        "kind": "property",
        "version": "0.1.0",
        "format": "1.3",
        "name": "heat_capacity_constant_volume",
        "label": "heat_capacity_constant_volume_thermodynamics_httk"
    },
    "x-optimade-unit": "K^-1*eV",
    "x-optimade-unit-definitions": [
        {
            "$id": "https://schemas.optimade.org/defs/v1.2/units/si/general/electronvolt",
            "title": "electron volt",
            "symbol": "eV",
            "display-symbol": "eV",
            "description": "A unit of energy that representing the kinetic energy acquired by an electron as it accelerates through a 1 volt potential difference in a vacuum using the current, or one of the historical, definitions given in the editions of the International System of Units (SI).\n\nThe electronvolt unit appears in the International System of Units (SI), 1st ed. (1970) defined as \"1 electronvolt is the energy acquired by an electron after traversing a potential difference of 1 V in a vacuum; 1 eV = 1.60219\u00d710\u207b\u00b9\u2079 J approximately.\"\nThis definition makes the unit equal to 1 volt times the value of the elementary charge.\nIn the 2019 redefinition of the SI units the elementary charge is exactly 1.602176634\u00b710\u207b\u00b9\u2079 C, making the electron volt exactly equal to 1.602176634\u00b710\u207b\u00b9\u2079 J.\nThe International System of Units (SI), 9th ed. (2019) accordingly notes the exact relationship with the SI 2019 derived unit joule as \"1 eV = 1.602176634\u00b710\u207b\u00b9\u2079 J\" but retains the definition from 1970 in a footnote.\n\nThe unit is categorized in the International System of Units (SI), 9th ed. (2019) as \"Non-SI units accepted for use with the SI units\".\n\nThis is a generalized definition taken to reference the current, or one of the historical, SI unit definitions.\nThis definition is intended for situations when it is not possible to be more precise, e.g., in contexts where data have been collected that uses different historical SI definitions.",
            "compatibility": [
                "https://schemas.optimade.org/defs/v1.2/units/si/1970/accepted/electronvolt",
                "https://schemas.optimade.org/defs/v1.2/units/si/1983/accepted/electronvolt",
                "https://schemas.optimade.org/defs/v1.2/units/si/2019/accepted/electronvolt"
            ],
            "resources": [
                {
                    "relation": "Definition in the International System of Units (SI), 9th Edition",
                    "resource-id": "https://www.bipm.org/en/publications/si-brochure"
                },
                {
                    "relation": "Wikipedia article describing the unit",
                    "resource-id": "https://en.wikipedia.org/wiki/Electronvolt"
                }
            ],
            "approximate-relations": [
                {
                    "base-units": [
                        {
                            "symbol": "V",
                            "id": "https://schemas.optimade.org/defs/v1.2/units/si/general/volt"
                        },
                        {
                            "symbol": "e",
                            "id": "https://schemas.optimade.org/defs/v1.2/constants/codata/2018/electromagnetic/elementarycharge"
                        }
                    ],
                    "base-units-expression": "e*V"
                }
            ],
            "x-optimade-definition": {
                "label": "electronvolt_si_general",
                "kind": "unit",
                "format": "1.2",
                "version": "1.2.0",
                "name": "electronvolt"
            }
        },
        {
            "$id": "https://schemas.optimade.org/defs/v1.2/units/si/general/kelvin",
            "title": "kelvin",
            "symbol": "K",
            "display-symbol": "K",
            "description": "A unit of thermodynamic temperature using the current, or one of the historical, definitions of the SI units.\n\nThe current definition at the 26th CGPM Meeting in 2018, resolution 1 is: \"The kelvin, symbol K, is the SI unit of thermodynamic temperature. It is defined by taking the fixed numerical value of the Boltzmann constant k to be 1.380649\u00d710\u207b\u00b2\u00b3 when expressed in the unit J\u22c5K\u207b\u00b9, which is equal to kg\u22c5m\u00b2\u22c5s\u207b\u00b2\u22c5K\u207b\u00b9, where the kilogram, metre and second are defined in terms of \\(h\\), \\(c\\) and \\(\\Delta \\nu_\\textrm{Cs}\\).\" [26th CGPM Meeting (2018), resolution 1].\n\nThe prior definition at the 13th CGPM Meeting in 1967, resolution 4, was: \"The kelvin, unit of thermodynamic temperature, is the fraction 1/273.16 of the thermodynamic temperature of the triple point of water.\"\nThis definition changed the symbol and rephrased the definition of the unit \"degree Kelvin\" from the 10th CGPM meeting in 1954: \"The 10th Conf\u00e9rence G\u00e9n\u00e9rale des Poids et Mesures decides to define the thermodynamic temperature scale by choosing the triple point of water as the fundamental fixed point, and assigning to it the temperature 273.16 degrees Kelvin, exactly.\"\n\nThis is a generalized definition taken to reference the current, or one of the historical, SI unit definitions.\nThis definition is intended for situations when it is not possible to be more precise, e.g., in contexts where data have been collected that uses different historical SI definitions.",
            "compatibility": [
                "https://schemas.optimade.org/defs/v1.2/units/si/1967/base/kelvin",
                "https://schemas.optimade.org/defs/v1.2/units/si/2019/base/kelvin",
                "https://schemas.optimade.org/defs/v1.2/units/si/1960/base/degreekelvin"
            ],
            "resources": [
                {
                    "relation": "Definition in the 26th CGPM Meeting in 2018, resolution 1",
                    "resource-id": "https://www.bipm.org/en/committees/cg/cgpm/26-2018/resolution-1"
                },
                {
                    "relation": "Definition in the International System of Units (SI), 9th Edition",
                    "resource-id": "https://www.bipm.org/en/publications/si-brochure"
                },
                {
                    "relation": "Wikipedia article describing the unit",
                    "resource-id": "https://en.wikipedia.org/wiki/Kelvin"
                }
            ],
            "x-optimade-definition": {
                "label": "kelvin_si_general",
                "kind": "unit",
                "format": "1.2",
                "version": "1.2.0",
                "name": "kelvin"
            }
        }
    ],
    "x-optimade-requirements": {
        "support": "may",
        "sortable": false,
        "query-support": "all mandatory"
    },
    "type": [
        "number",
        "null"
    ],
    "description": "The heat capacity at constant volume C_V, in electronvolt per kelvin (eV K^-1).\nExtensive quantity of the whole simulated cell. It may be obtained, e.g., from canonical-ensemble energy fluctuations as Var(E) / (kB T^2), at the temperature recorded alongside.\nA null value means the quantity is not available or not recorded."
}