Fluorine energy level diagram

Energy levels and transitions of neutral fluorine (F I): the 46 strongest classified lines below 2 µm from the NIST Atomic Spectra Database and the 27 levels they connect, each line with its vacuum wavelength, frequency and, for 46 of them, the reduced dipole matrix element derived from the NIST transition rate. Measured lifetimes, transition rates, hyperfine constants and isotope shifts from the literature are included, each with its citation.

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Download: diagram (PDF) diagram (SVG) transitions (CSV) levels (CSV) source code

Key transitions of fluorine

λ, ν from NIST level energies unless a measured frequency for this isotope is available. A: measured value or NIST. Γ/2π: natural linewidth of the upper level, 1/(2πτ).

¹⁹F hyperfine structure (I = 1/2)

Measured A, B constants; sources in the data file.

Listed F transitions below 2 µm

Reduced dipole matrix elements follow the convention A = ω³|d|²/(3πε₀ħc³(2J′+1)), with J′ the upper level. Tags show where a number comes from: measured, NIST compilation, high-accuracy theory, a semi-empirical calculation (Kurucz line list, used only where no measurement or NIST value exists; typically within a factor 2), or a model calculation.

F energy levels

F⁺ ionisation limit 140524.50 cm⁻¹ = 17.42282 eV (71.162 nm)

Sources

• Harvey, Proc. R. Soc. Lond. A 285, 581 (1965), abstract (paramagnetic resonance)
• Huo, Deng, Windholz, Mu, Wang, J. Quant. Spectrosc. Radiat. Transfer 205, 1 (2018) (conce…
• Huo, Deng, Windholz, Mu, Wang, J. Quant. Spectrosc. Radiat. Transfer 205, 1 (2018), as qu…
• Kurucz, R. L., Can. J. Phys. 89, 417 (2011); semi-empirical line list gf0900.pos of 2015-…
• Levy, Cocolios, Behr, Jayamanna, Minamisono, Pearson, Nucl. Instrum. Methods A 580, 1571 …
• NIST ASD
• NIST ASD F I lines table with forbidden lines (24.74 um M1, A = 1.187e-3 s^-1, accuracy A…
• NIST ASD level energies
• Radford, Hughes, Beltran-Lopez, Phys. Rev. 123, 153 (1961), as tabulated in Table II of A…
• Shimizu, Ohmi, Kakiuchi, Yasutake, J. Vac. Sci. Technol. A 24, 2133 (2006), abstract (res…
• Tate & Aturaliye, Phys. Rev. A 56, 1844 (1997) (Doppler-free saturated absorption, diode …
• Tate & Aturaliye, Phys. Rev. A 56, 1844 (1997), as tabulated in Carette, Nemouchi, Li, Go…
• hyperfine centre of gravity 14581.684 cm^-1 from Liden, Ark. Fys. 1, 229 (1949), as quote…

Level energies are NIST ASD values. 19F: I = 1/2, so only magnetic-dipole constants A exist (no B). The 3d-level A values (Huo et al. 2018) are second-hand from the theory paper arXiv:2108.01116 and carry about 5 % uncertainty. Lifetime of the metastable 3s 4P5/2 level: the Elsevier text of Levy et al. prints the unit with a symbol-font glyph ("ms"); it is microseconds, as the abstract of Shimizu et al. 2006 states explicitly (7.3 +- 0.5 us). The frequency of the 685.6 nm line is an old (1949) value quoted second-hand; treat it as a consistency check of the NIST Ritz value, not as a precision measurement. Sources were located through arXiv/DataCite, CORE, HAL, Crossref and publisher abstract pages; the web-search quota of the session was exhausted, so coverage is limited to what those indexes exposed.

Atoms with measured data

• Lithium-632 levels, 85 lines
• Lithium-732 levels, 85 lines
• Beryllium-917 levels, 26 lines
• Sodium-2336 levels, 106 lines
• Magnesium-2418 levels, 61 lines
• Magnesium-2518 levels, 61 lines
• Potassium-3934 levels, 84 lines
• Potassium-4034 levels, 84 lines
• Potassium-4134 levels, 84 lines
• Calcium-4035 levels, 61 lines
• Calcium-4335 levels, 61 lines
• Chromium-5256 levels, 87 lines
• Chromium-5356 levels, 87 lines
• Rubidium-8536 levels, 94 lines
• Rubidium-8736 levels, 94 lines
• Strontium-8440 levels, 70 lines
• Strontium-8640 levels, 70 lines
• Strontium-8740 levels, 70 lines
• Strontium-8840 levels, 70 lines
• Cadmium-11115 levels, 21 lines
• Cadmium-11315 levels, 21 lines
• Cadmium-11415 levels, 21 lines
• Caesium-13331 levels, 79 lines
• Barium-13744 levels, 89 lines
• Barium-13844 levels, 89 lines
• Dysprosium-16139 levels, 55 lines
• Dysprosium-16239 levels, 55 lines
• Dysprosium-16339 levels, 55 lines
• Dysprosium-16439 levels, 55 lines
• Erbium-16673 levels, 90 lines
• Erbium-16773 levels, 90 lines
• Erbium-16873 levels, 90 lines
• Thulium-16972 levels, 73 lines
• Ytterbium-17118 levels, 26 lines
• Ytterbium-17318 levels, 26 lines
• Ytterbium-17418 levels, 26 lines
• Mercury-19927 levels, 47 lines
• Mercury-20127 levels, 47 lines
• Mercury-20227 levels, 47 lines

All elements: periodic table