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Bohr hydrogen energy levels and emission spectrum

What you are seeing: the hydrogen energy ladder En=13.6eV/n2E_n = -13.6\,\mathrm{eV}/n^2 on the left, and the spectrum on the right. Each emission line nhnn_h \to n_\ell corresponds to a photon of wavelength 1/λ=RH(1/n21/nh2)1/\lambda = R_H (1/n_\ell^2 - 1/n_h^2), where RH1.0968×107m1R_H \approx 1.0968 \times 10^7 \, \mathrm{m}^{-1} is the hydrogen Rydberg constant (proton mass correction included).

The Lyman series (n=1n_\ell = 1) lives in the UV and converges at 91.2 nm; the Balmer series (n=2n_\ell = 2) is in the visible and converges at 365 nm; the Paschen series (n=3n_\ell = 3) lies in the near IR. Select a series with the dropdown to highlight only its transitions and emphasise its series limit. The Bohr formula matches observed wavelengths to a few parts in 10410^4; the residual is the fine structure (Dirac equation plus QED corrections) that the classical Bohr model cannot capture.

Figure 1. Bohr hydrogen energy levels and emission spectrum. Method: closed-form Rydberg 1/λ=RH(1/n21/nh2)1/\lambda = R_H (1/n_\ell^2 - 1/n_h^2) with proton-mass corrected RHR_H.
series Balmer
n_max8
highlight line3->2

WHAT TO TRY

  • Vary each control and watch the rail readouts respond.
  • Compare the diagnostic plot against the live scene.