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Rydberg constant
Intermediate
Constant in the spectral formula.
R = 1.097×10⁷ m⁻¹R = 1.097×10⁷ m⁻¹ appears in the spectral formula; theoretically R = mₑe⁴/(8ε₀²h³c).
Lyman limit: λ = 1/R = 91.2 nm.
Small correction for nuclear mass.
In more detail
The Rydberg constant R ≈ 1.097 × 10⁷ per metre links wavelengths of hydrogen lines through 1/λ = R(1/n1² − 1/n2²). It appears in many spectroscopic formulas.
Real-world uses
- Spectroscopists use the Rydberg formula to predict line positions.
- Measurements of R test quantum theory precisely.
- Spectroscopists use the Rydberg constant to predict the wavelengths of hydrogen-like lines in a spectrometer.
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Frequently asked questions
Is it the same for all elements?
It is modified for other elements, but the form of the formula remains.
Why is the constant important?
It depends on fundamental constants and can be measured very precisely.
Does the Rydberg constant depend on the element?
It applies to hydrogen; with a small correction for the nuclear mass, it works for other hydrogen-like ions.
Related topics in Atomic & Nuclear Physics
Radius of Bohr orbit · Energy of hydrogen levels · Hydrogen spectrum · Absorption and emission spectra · Ionisation energy · Franck–Hertz experiment