Bohr radius
m
The Bohr radius is the most probable distance of the electron from the nucleus in a ground-state hydrogen atom. It sets the natural length scale of atoms — all atomic sizes are roughly a few Bohr radii.
Used in
- Atomic size estimates (~0.5 Å per Bohr radius)
- Bohr model energy levels E_n = −13.6 eV/n²
Source: SI defining constants / CODATA 2018