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

Shear viscosity (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/transport/shear_viscosity
Definition name: shear_viscosity

Property name: Shear viscosity
Description: The shear viscosity, in pascal second (Pa s). Obtained from Green-Kubo or Einstein relations. By the Green-Kubo relation eta = V / (kB T) times the time integral of , averaged over the independent off-diagonal stress components. 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:

{
    "$id": "https://schemas.httk.org/defs/v0.1/properties/transport/shear_viscosity",
    "$schema": "https://schemas.optimade.org/meta/v1.3/optimade/property_definition.json",
    "title": "Shear viscosity",
    "x-optimade-type": "float",
    "x-optimade-definition": {
        "kind": "property",
        "version": "0.1.0",
        "format": "1.3",
        "name": "shear_viscosity",
        "label": "shear_viscosity_transport_httk"
    },
    "x-optimade-unit": "Pa*s",
    "x-optimade-unit-definitions": [
        {
            "$id": "https://schemas.optimade.org/defs/v1.2/units/si/general/pascal",
            "title": "pascal",
            "symbol": "Pa",
            "display-symbol": "Pa",
            "description": "A unit for pressure and stress equal to kg\u00b7m\u207b\u00b9\u00b7s\u207b\u00b2 using the current, or one of the historical, definitions of the SI units.\n\n\"The International Committee will ask the General Conference to approve two special names: pascal (symbol Pa) for the SI unit of pressure (N/m\u00b2), [...]\" [14th CGPM Meeting (1971)].\n\nThe pascal was defined at the 14th CGPM Meeting in 1971 and implicitly redefined via the redefinitions of the metre at the 17th CGPM Meeting in 1983, resolution 1, and the kilogram at the 26th CGPM Meeting (2018), resolution 1.\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/1971/named/pascal",
                "https://schemas.optimade.org/defs/v1.2/units/si/1983/named/pascal",
                "https://schemas.optimade.org/defs/v1.2/units/si/2019/named/pascal"
            ],
            "resources": [
                {
                    "relation": "Definition at the 14th CGPM Meeting (1971)",
                    "resource-id": "https://www.bipm.org/en/committees/cg/cgpm/14-1971"
                },
                {
                    "relation": "Wikipedia article describing the unit",
                    "resource-id": "https://en.wikipedia.org/wiki/Pascal_(unit)"
                },
                {
                    "relation": "Redefinition of the metre at the 17th CGPM meeting (1983), resolution 1",
                    "resource-id": "https://www.bipm.org/en/committees/cg/cgpm/17-1983/resolution-1"
                },
                {
                    "relation": "Redefinition of the kilogram at the 26th CGPM Meeting (2018), resolution 1",
                    "resource-id": "https://www.bipm.org/en/committees/cg/cgpm/26-2018/resolution-1"
                }
            ],
            "defining-relation": {
                "base-units": [
                    {
                        "symbol": "kg",
                        "id": "https://schemas.optimade.org/defs/v1.2/units/si/general/kilogram"
                    },
                    {
                        "symbol": "m",
                        "id": "https://schemas.optimade.org/defs/v1.2/units/si/general/metre"
                    },
                    {
                        "symbol": "s",
                        "id": "https://schemas.optimade.org/defs/v1.2/units/si/general/second"
                    }
                ],
                "base-units-expression": "kg*m^-1*s^-2"
            },
            "x-optimade-definition": {
                "label": "pascal_si_general",
                "kind": "unit",
                "format": "1.2",
                "version": "1.2.0",
                "name": "pascal"
            }
        },
        {
            "$id": "https://schemas.optimade.org/defs/v1.2/units/si/general/second",
            "title": "second",
            "symbol": "s",
            "display-symbol": "s",
            "description": "A unit of time using the current, or one of the historical, definitions of the SI units.\n\nThe current definition in its most recent phrasing at the 26th CGPM Meeting in 2018, resolution 1 is: \"The second, symbol s, is the SI unit of time. It is defined by taking the fixed numerical value of the caesium frequency, \\(\\Delta \\nu_\\textrm{Cs}\\), the unperturbed ground-state hyperfine transition frequency of the caesium 133 atom, to be 9192631770 when expressed in the unit Hz, which is equal to s\u207b\u00b9.\"\n\nThis is a rephrasing of a definition at the 13th CGPM Meeting (1967), resolution 1: \"The second is the duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.\"\n\nThe earlier definition at the 11th CGPM Meeting in 1960, resolution 9 was: \"The second is the fraction 1/31556925.9747 of the tropical year for 1900 January 0 at 12 hours ephemeris time.\"\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/1960/base/second",
                "https://schemas.optimade.org/defs/v1.2/units/si/1967/base/second"
            ],
            "resources": [
                {
                    "relation": "Definition in the 13th CGPM Meeting (1967), resolution 1",
                    "resource-id": "https://www.bipm.org/en/committees/cg/cgpm/13-1967/resolution-1"
                },
                {
                    "relation": "Rephrased definition in the 26th CGPM Meeting (2018), resolution 1",
                    "resource-id": "https://www.bipm.org/en/committees/cg/cgpm/26-2018/resolution-1"
                },
                {
                    "relation": "Definition at the 11th CGPM meeting (1960), resolution 6.",
                    "resource-id": "https://www.bipm.org/en/committees/cg/cgpm/11-1960/resolution-6"
                },
                {
                    "relation": "Wikipedia article describing the unit",
                    "resource-id": "https://en.wikipedia.org/wiki/Second"
                }
            ],
            "x-optimade-definition": {
                "label": "second_si_general",
                "kind": "unit",
                "format": "1.2",
                "version": "1.2.0",
                "name": "second"
            }
        }
    ],
    "x-optimade-requirements": {
        "support": "may",
        "sortable": false,
        "query-support": "all mandatory"
    },
    "type": [
        "number",
        "null"
    ],
    "description": "The shear viscosity, in pascal second (Pa s).\nObtained from Green-Kubo or Einstein relations. By the Green-Kubo relation eta = V / (kB T) times the time integral of <sigma_xy(0) sigma_xy(t)>, averaged over the independent off-diagonal stress components.\nA null value means the quantity is not available or not recorded."
}