Strong spectral lines of the elements
The strongest emission lines of 99 elements, from hydrogen to einsteinium, as tabulated in NIST's Handbook of Basic Atomic Spectroscopic Data. One row per spectral line: element, ion stage, wavelength, relative intensity and whether it is a persistent line.
Columns
Stable keys — use them in the API, SQL and code
| Key | Name | Type | Description |
|---|---|---|---|
| line_id | ID | string | Spectrum, medium and wavelength. |
| atomic_number | Atomic number | integer | — |
| element | Element | string | — |
| symbol | Symbol | string | — |
| spectrum | Spectrum | string | Element and ion stage in spectroscopic notation: Fe I is neutral iron, Fe II singly ionized iron. |
| ion_stage | Ion stage | integer | 1 = neutral atom (I), 2 = singly ionized (II), and so on. |
| wavelength_angstrom | Wavelength (Å) | number · Å | Wavelength as given by NIST, in ångströms. |
| wavelength_nm | Wavelength | number · nm | Wavelength in nanometres (Å ÷ 10). |
| medium | Medium | string | Whether the wavelength is measured in vacuum or standard air. |
| intensity | Relative intensity | number | Relative intensity on the element's own scale. |
| persistent | Persistent line | boolean | NIST marks this as a persistent line (P). |
| intensity_marks | Intensity marks | string | Other NIST intensity codes for the line, if any. |
| reference | Reference | string | NIST Handbook bibliography code for the wavelength. |
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