Bohr radius = 5.291 772 105 44 × 10−11 m
- Symbol
- a₀
- Value
- 5.291 772 105 44 × 10−11
- Unit
- m
- Uncertainty
- 0.000 000 000 82 × 10⁻¹¹
- Copy-ready
5.29177210544e-11
The natural length scale of the hydrogen atom — roughly half an ångström.
NIST, Fundamental Physical Constants — Complete Listing (2022 CODATA adjustment), retrieved 2026-07-26.
Atomic and electromagnetic constants
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