What is the Rydberg energy?
The Rydberg energy is Ry = 2.1798723611035e-18 J (uncertainty ±4.2e-30), equal to 13.605693122994 eV. It is the hydrogen ionization energy.
Open the interactive PhysRef tool →Key facts
| Value | 2.1798723611035e-18 J |
|---|---|
| Symbol | Ry |
| In eV | 13.605693122994 eV |
| Uncertainty | ±4.2e-30 J |
| Source | CODATA 2018 |
Frequently asked questions
What is the Rydberg energy in eV?
Ry = 13.605693122994 eV, the ionization energy of hydrogen from its ground state (infinite-mass approximation).
What is the Rydberg energy in joules?
Ry = 2.1798723611035e-18 J.
How does Ry relate to the Hartree?
One Hartree equals two Rydberg energies, so Ry = E_h/2.
Related pages
Rydberg energy is part of PhysRef on GOAT Lab — a free reference you can use without signing up, and it works offline. Open the tool above for any custom value.
Part of GOAT Lab — 26 free, browser-based science, engineering and developer tools. No sign-up.