rupper_2004

P. Rupper and F. Merkt, “Intense narrow-bandwidth extreme ultraviolet laser system tunable up to 20 eV”, Rev. Sci. Instrum. 75, 613 (2004)

Source record · Catalogue · Review register

DOI: 10.1063/1.1646744

Source kind: measurement

Recorded technique: Resonance-enhanced sum- and difference-frequency four-wave mixing in a pulsed argon jet (3 bar stagnation): the five two-photon resonances 3p5 4p <- 3p6 1S0 of argon (105 000-109 000 cm^-1) reached with one F2 excimer photon (63 439.322 cm^-1, about 30 ns, 1.5-2.0 mJ) plus one frequency-tripled dye-laser photon (about 0.8 mJ at 230 nm), mixed with a second dye laser (nu_VUV = nu_1 + nu_Ex +- nu_2); the VUV/XUV separated by a toroidal-grating monochromator. Applications by PFI-ZEKE photoelectron spectroscopy in skimmed supersonic beams (about 6 K rotational temperature): the 21Ne/22Ne isotope shift of the 2p5 4s[3/2]1 line, acetylene near 92 000 cm^-1, CO2 between 140 000 and 146 000 cm^-1.

Materials in structured entries: CO2

Dataset quantities: ionization_energy

Contents: 2 datasets; 0 formulas.

Curation notes

Pages: the library PDF has a publisher cover page; PDF page n is journal page 611 + n (pp. 613-622). Identity checked against PDF p. 2 (Rev. Sci. Instrum. 75, No. 3, March 2004). Wave numbers in vacuum cm^-1 as printed.

WHAT IS TAKEN: the first adiabatic ionisation energy of CO2 (X 2Pi_3/2g (0,0,0) J+ = 3/2 <- X 1Sigma_g+ (0,0,0) J’’ = 0), as text points. The paper prints three values: the abstract’s 111 112.3 +- 0.8 cm^-1 (p. 613, ‘Improved values ... were determined’), and two derivations in Sec. IV C: 111 112.0 +- 0.8 cm^-1 from the PFI-ZEKE A 2Pi_3/2u (0,0,0) J+ = 3/2 ionisation energy, 139 644.5(8) cm^-1, minus the A-X interval of Johnson and Rostas (Ref. 52; p. 621), and 111 112.7 +- 1.0 cm^-1 from the B 2Sigma_u+ (0,0,0) photoelectron spectrum with the B-X band wave numbers of Watson et al. (Ref. 51; p. 622). The abstract’s value is the dataset adiabatic_CO2; the paper does not say how it is formed: the inverse-variance mean of the two derivations is 111 112.27 cm^-1 (+-0.62), consistent with it (computed 2026-10-08), but the abstract’s +-0.8 is the A route’s. The two derivations are the check dataset adiabatic_CO2_routes. Earlier values quoted: 111 113 +- 2 (Ref. 16, Wiedmann et al.) and 111 111 +- 3 cm^-1 (Ref. 38, Merkt et al. 1993) (p. 621). Both routes depend on others’ optical spectroscopy of CO2+ for the interval to the X state.

NOT TAKEN. (1) Table I (p. 616, tbl_3a949542b2fb, checked against the image), the five argon two-photon resonances 4p[5/2]2, 4p[3/2]2, 4p[1/2]0, 4p’[3/2]2, 4p’[1/2]0: nu_1, nu_Ex, nu_res = nu_1 + nu_Ex = 105 617.54(60), 106 237.56(60), 107 054.24(14), 107 289.71(60), 108 722.65(17) cm^-1 (this work), Minnhagen’s term values 105 617.2700, 106 237.5518, 107 054.2720, 107 289.7001, 108 722.6194 cm^-1 (Ref. 20, J. Opt. Soc. Am. 63, 1185 (1973), +-0.05 cm^-1), FWHM 0.54, 0.59, 0.67, 0.60, 0.65 cm^-1, and relative four-wave-mixing conversion efficiencies 1.2(2), 1 (reference), 4.0(12), 1.0(2), 7.5(24); with the second F2 line, 4p’[1/2]0 at 108 722.79(60) cm^-1, FWHM 0.56 cm^-1. The positions are level energies measured through the F2 line wave numbers of Sansonetti et al. (Ref. 24), less precise than Minnhagen’s, which are NIST’s strings (nist_asd_2026 level_Ar_even_J2 105617.2700 and level_Ar_even_J0 107054.2720; the others are rows of NIST Ar_I_levels.tsv, identical); the widths are laser bandwidths (the excimer’s about 0.3, the tripled dye laser’s 0.45 cm^-1, Doppler about 0.13 cm^-1; ac Stark broadening minor, p. 616); the efficiencies are relative four-wave-mixing outputs (+-30 %, mostly excimer energy and overlap), not cross sections. (2) The F2 laser and argon’s two-photon ionisation: the main F2 line, 63 439.322(40) cm^-1, is 157.6308 nm (vacuum) and the second, 63 482.257(40) cm^-1, 157.5242 nm (computed 2026-10-08); two-photon ionisation of Ar needs lambda < 157.344 nm (hc over half of nist_asd_2026’s ie_Ar_I, 15.7596119 eV = 127 109.84 cm^-1): two photons of the main line (126 878.64 cm^-1) fall 231 cm^-1 short of the threshold, of the second line 145 cm^-1. The paper attributes a dip of the XUV output near the Ar 3p5 5d[3/2]1 resonance (Fig. 4, p. 617) to ‘doubly resonant multiphoton ionization of argon in the four-wave mixing region by the input lasers’; no rate is given. (3) Table II (p. 617), VUV/XUV photons per pulse: instrument output. (4) The first adiabatic ionisation energy of acetylene, 91 953.5(5) cm^-1 (abstract, Table III): C2H2 is not a registered material. (5) CO2+ A-state ionisation energies (Table IV, p. 621: 139 644.5(8), 140 771.6(8), 141 893.9(8) cm^-1 for v1 = 0-2) and the B state’s (145 782 +- 1 (3ef), 145 791 +- 1 (2ef), deperturbed 145 786.3 +- 1.0 cm^-1; p. 622): ionisation energies to excited states of the ion, not the first ionisation energy this record holds; Table IV would need an extraction script; not taken here. Neon’s isotope shift (Sec. IV A) is not a quantity.

FURTHER TWO-PHOTON DATA CITED: the Kr 4p5 5p[1/2]0 and 5p’[1/2]0 (94 092.862 and 98 855.071 cm^-1) and Xe 5p5 6p[1/2]0 and 6p’[1/2]0 (80 118.974 and 89 860.038 cm^-1) two-photon resonances (p. 613-614), positions only, from Moore (Ref. 12), T. Trickl, M. J. J. Vrakking, E. Cromwell, Y. T. Lee and A. H. Kung, Phys. Rev. A 39, 2948 (1989) (Ref. 13) and K. Yoshino and D. E. Freeman, J. Opt. Soc. Am. B 2, 1268 (1985) (Ref. 14); the weaker Ar 4p[5/2]2 resonance at 189.3 nm used by H. Palm and F. Merkt, Appl. Phys. Lett. 73, 157 (1998) (Ref. 21). No two-photon cross section is cited.

Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.

Datasets

rupper_2004/adiabatic_CO2

{
  "id": "adiabatic_CO2",
  "material": "CO2",
  "table": "text",
  "quantity": "ionization_energy",
  "unit": "cm-1",
  "abscissa": "label",
  "use": "primary",
  "parameters": {
    "kind": "adiabatic",
    "final_state": "X 2Pi_3/2g (0,0,0) J+ = 3/2, from X 1Sigma_g+ (0,0,0) J'' = 0"
  },
  "uncertainty": {
    "column": true,
    "level": "not stated"
  }
}

1 inline points in the source record.

Abstract, p. 613: ‘Improved values of the first adiabatic ionization energy of ... CO2 (111 112.3 +- 0.8 cm^-1) were determined’. Level of +-0.8 not stated. The text’s two derivations are adiabatic_CO2_routes (see the record’s notes).

rupper_2004/adiabatic_CO2_routes

{
  "id": "adiabatic_CO2_routes",
  "material": "CO2",
  "table": "text",
  "quantity": "ionization_energy",
  "unit": "cm-1",
  "abscissa": "label",
  "use": "check",
  "parameters": {
    "kind": "adiabatic",
    "final_state": "X 2Pi_3/2g (0,0,0) J+ = 3/2, from X 1Sigma_g+ (0,0,0) J'' = 0"
  },
  "uncertainty": {
    "column": true,
    "level": "not stated"
  }
}

2 inline points in the source record.

Sec. IV C: row A, p. 621, ‘Subtracting from the adiabatic ionization energy the energy difference between the A 2Pi_3/2u(0,0,0) J+ = 3/2 and the X 2Pi_3/2g(0,0,0) J+ = 3/2 states ... (Ref. 52) leads to a value for the first adiabatic ionization energy of CO2 of 111 112.0 +- 0.8 cm^-1’; row B, p. 622, from the B 2Sigma_u+ (0,0,0) photoelectron spectrum with the B-X band system (Ref. 51), ‘A value of 111 112.7 +- 1.0 cm^-1 is found’. Two derivations of the abstract’s value (adiabatic_CO2), each through an interval from others’ optical spectroscopy; levels not stated.

Formulas

No formulas are recorded.

Corrections

No dataset errata are recorded in this source record.

Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the review register for the checks and decisions.