Praseodymium energy level diagram

Energy levels and transitions of neutral praseodymium (Pr I): the 74 strongest classified lines below 2 µm from the NIST Atomic Spectra Database and the 97 levels they connect, each line with its vacuum wavelength, frequency and, for 0 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 praseodymium

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).

¹⁴¹Pr hyperfine structure (I = 5/2)

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

Listed Pr 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, or a model calculation.

Pr energy levels

Pr⁺ ionisation limit 44120.00 cm⁻¹ = 5.47018 eV (226.655 nm)

Sources

• Biémont, Quinet, Svanberg, Xu, J. Phys. B 37, 1381 (2004), Table 1
• Childs & Goodman, Phys. Rev. A 24, 1342 (1981), atomic-beam laser-rf double resonance, as…
• Guthöhrlein (1996-2005), unpublished diploma theses, Helmut-Schmidt-Universität Hamburg, …
• Kuwamoto et al. (1996), atomic-beam laser spectroscopy, as tabulated in Khan, Siddiqui, I…
• NIST ASD level energies

141Pr is the only stable isotope (I = 5/2); there are no isotope shifts to report. Hyperfine constants: second-hand from the reference columns of Khan et al., Int. J. Chem. 9(1), 7 (2017) (open-access PDF parsed as text), which quote Childs & Goodman 1981 (CG81, laser-rf double resonance, kHz-level precision, printed without uncertainty), Kuwamoto et al. 1996 (K96), Krzykowski et al. 1997 (KF97) and unpublished Hamburg theses (G96). Where the source assumed B = 0 no B is given. Classified lines: (a) Gamper et al., J. Phys. B 44, 045003 (2011), supplementary Table 1 (PDF downloaded through the publisher data page): air centre-of-gravity wavelengths in angstrom, signal-to-noise ratio, J and energy of the even and odd level. Only lines whose two levels match NIST levels (same J, energy within 0.15 cm-1, expected parity) were entered. The supplementary table carries no caption stating air/vacuum; the wavelengths reproduce the level differences only as air wavelengths (checked on 4432.240 - 29526.571: vacuum 3984.96 A, listed 3983.837 A). (b) the excitation schemes of Biémont et al. 2004, Table 1 (vacuum wavelengths computed from NIST energies). "relative_intensity" is a non-schema field holding the signal-to-noise ratio. Laser stabilisation (not entered as transitions because the levels are not in NIST): Oppel, Guthöhrlein, Kaenders, von Zanthier, arXiv:0912.2234 lock a diode laser to the Pr I line 16502.616 (J=7/2, even) - 25442.742 (J=9/2, odd) cm-1 at 1118.5397(4) nm, and show

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