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

**ID: https://schemas.optimade.org/defs/v1.2/units/si/general/curie**

`curie`

**Unit name:** curie

**Latin symbol:** Ci

**Display symbol:** Ci

**Description:** A unit of activity with the value 3.7·10⁻¹⁰ s⁻¹ using the current, or one of the historical, definitions of the SI units.

Defined as outside the SI at the 12th CGPM meeting in 1964, resolution 7. Implicitly redefined via the redefinition of the second at the 13th CGPM Meeting in 1967, resolution 1.

- The International System of Units (SI), 1st ed. (1970) categorizes the unit as "Units in use temporarily with the International System."
- The International System of Units (SI), 7th ed. (1998) changes the categorization to "Other non-SI units".
- The curie is omitted in the International System of Units (SI), 8th Edition (2006).

This is a generalized definition taken to reference the current, or one of the historical, SI unit definitions. This 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.

**Resources:**

- Definition at the 12th CGPM meeting (1964), resolution 3
- Redefinition of the second in the 13th CGPM Meeting (1967), resolution 1
- Le Système International d'Unités (SI) (1970)
- Wikipedia article describing the unit

**Compatibility:** (other definitions that are covered by the above definition)

`https://schemas.optimade.org/defs/v1.2/units/si/1964/temporary/curie`

`https://schemas.optimade.org/defs/v1.2/units/si/1967/temporary/curie`

**JSON definition:**

```
{
"$id": "https://schemas.optimade.org/defs/v1.2/units/si/general/curie",
"$schema": "https://schemas.optimade.org/meta/v1.2/optimade/physical_unit_definition.json",
"title": "curie",
"symbol": "Ci",
"display-symbol": "Ci",
"description": "A unit of activity with the value 3.7\u00b710\u207b\u00b9\u2070 s\u207b\u00b9 using the current, or one of the historical, definitions of the SI units.\n\nDefined as outside the SI at the 12th CGPM meeting in 1964, resolution 7.\nImplicitly redefined via the redefinition of the second at the 13th CGPM Meeting in 1967, resolution 1.\n\n- The International System of Units (SI), 1st ed. (1970) categorizes the unit as \"Units in use temporarily with the International System.\"\n- The International System of Units (SI), 7th ed. (1998) changes the categorization to \"Other non-SI units\".\n- The curie is omitted in the International System of Units (SI), 8th Edition (2006).\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/1964/temporary/curie",
"https://schemas.optimade.org/defs/v1.2/units/si/1967/temporary/curie"
],
"resources": [
{
"relation": "Definition at the 12th CGPM meeting (1964), resolution 3",
"resource-id": "https://www.bipm.org/en/committees/cg/cgpm/12-1964/resolution-3"
},
{
"relation": "Redefinition of the second in the 13th CGPM Meeting (1967), resolution 1",
"resource-id": "https://www.bipm.org/en/committees/cg/cgpm/13-1967/resolution-1"
},
{
"relation": "Le Syst\u00e8me International d'Unit\u00e9s (SI) (1970)",
"resource-id": "https://www.bipm.org/en/publications/si-brochure"
},
{
"relation": "Wikipedia article describing the unit",
"resource-id": "https://en.wikipedia.org/wiki/Curie_(unit)"
}
],
"defining-relation": {
"base-units": [
{
"symbol": "s",
"id": "https://schemas.optimade.org/defs/v1.2/units/si/general/second"
}
],
"base-units-expression": "s^-1",
"scale": {
"numerator": 37,
"exponent": -11
}
},
"x-optimade-definition": {
"label": "curie_si_general",
"kind": "unit",
"format": "1.2",
"version": "1.2.0",
"name": "curie"
}
}
```