Hydrogen Spectrum

Select a series or custom transition. Upper/lower levels define emission: nᵢ > nƒ. The table buttons select lines and highlight the associated arrow. Standard series show transitions up to n=8 plus a selected higher level; custom input supports n≤30. Equal levels and upward transitions are rejected, never silently corrected.

The nonrelativistic Rydberg model includes reduced electron/proton mass using CODATA2022 constants. Level energies and photon energy use the same Rydberg constant, so ΔE=hc/λ. Wavelengths are in vacuum; commonly quoted air wavelengths differ (Hα around656.28nm in air versus about656.47nm here). Fine/hyperfine structure, Lamb shift and external fields are omitted; this is not a precision line database.

The energy axis is linear from the ground state to the zero-energy ionisation limit. Closely spaced level labels are moved with connector lines; actual level spacing remains physical. The lower strip plots wavelength positions on an adaptive linear axis, not measured intensity. UV/IR use neutral colours; visible colours are illustrative. CSV contains full model values.

Transition detail expands the selected energy interval on a linear scale; levels outside that interval are omitted. It does not change any energies or wavelengths. Click near a spectral line to select it, or use the table buttons with the keyboard. The dashed strip marker is the series limit. Only the series and entered upper/lower levels are retained; plots and the detail view are not saved.