1 electronvolt
1 eVEnergy · definition
The quantity is exact as entered. Comparisons use the clearly stated specimen, model or nominal measurement.
Energy
Just how much energy is 1 electronvolt?
Molecular
1 eV
1.6022 × 10⁻¹⁹ Jjoules
4.4505 × 10⁻²⁶ kWhkilowatt-hours
3.8293 × 10⁻²³ kcalkilocalories
01
1 electronvolt1 eVEnergy · definition
02
Strontium-87 optical clock transition1.779 eVClock-transition photon energy · measured reference · range 1.773 eV–1.785 eV
Bar length represents energy. Equal energy does not imply the same temperature, power or usefulness.
A little perspective
The clock-transition photon energy of Strontium-87 optical clock transition is about 1.78 times the energy of 1 electronvolt.
Measurements, assumptions & sources +
1 electronvolt
The quantity is exact as entered. Comparisons use the clearly stated specimen, model or nominal measurement.
Strontium-87 optical clock transition
The strontium-87 optical clock transition carries photon energy near 2.85 × 10⁻¹⁹ J. Frequency shifts depend on controlled experimental conditions.
NIST — Compact strontium optical clock
The marked clock-transition photon energy is calibrated. Unmeasured illustration details are representative.
Measurement details
Why these numbers?
The visual compares energy with clock-transition photon energy. The records below preserve each value’s basis and caveats.
Strontium-87 optical clock transition
1.779 eVClock-transition photon energy · measured reference · range 1.773 eV–1.785 eV
The strontium-87 optical clock transition carries photon energy near 2.85 × 10⁻¹⁹ J. Frequency shifts depend on controlled experimental conditions.
- Comparing
- Energy ↔ Clock-transition photon energy
- Relative size
- Strontium-87 optical clock transition is larger on this measurement by a factor of about 1.78. Strontium-87 optical clock transition's selected measurement is approximately 77.9% greater than 1 electronvolt's.
How to read the visual
The labelled spans and stored measurements determine the scale; unmeasured illustration details do not.
- Strontium-87 optical clock transition uses a 1.779 eV central value within a recorded range of 1.773 eV–1.785 eV.
- Strontium-87 optical clock transition is labelled measured reference; treat the displayed value as a comparison anchor rather than false precision.
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