hyman_1977#

H. A. Hyman, “Photoionization cross sections for excited states of argon and krypton”, Appl. Phys. Lett. 31, 14 (1977)

Source record · Catalogue · Review register

Source kind: theory

Recorded technique: Calculated one-photon photoionisation cross sections of the excited Ar(4s), Ar(4p), Kr(5s) and Kr(5p) states for the KrF laser (Eq. 1, sigma = 2.69e-18 (I + epsilon) x the l +- 1 radial matrix elements squared, energies in Ry): a central-field model, the bound and continuum orbitals of one potential, the parent ion’s potential from Clementi and Roetti’s Hartree-Fock functions plus a polarisation potential alpha / (r^2 + r0^2)^2 (Ar: r0 = 1.56 a0, alpha = 8.85 a0^3; Kr: r0 = 1.84 a0, alpha = 14.9 a0^3; Eq. 4, p. 15). Spin-orbit effects are neglected: the two series converging on the 2P3/2 and 2P1/2 ions are ‘effectively collapsed into one series of levels’ averaged over the total angular momentum and the core state (p. 14).

Materials in structured entries: Ar, Kr

Dataset quantities: excited_state_photoionization_cross_section

Contents: 4 datasets; 0 formulas.

Curation notes#

Appl. Phys. Lett. 31(1), 14-15 (1 July 1977) = PDF pages 2-3 of AIP’s download, behind AIP’s cover page (PDF p. 1); scanned pages, each one image with a text layer. Identity checked against the first page of the article (journal, volume, pages, date, title, author). Table I checked against the table image and the rendered page (p. 15).

LEVELS. Each ‘state’ is a configuration average: Ar(4p) is 3p5 4p, Kr(5p) 4p5 5p, averaged over J and over the two core states (p. 14); Ar(4s) and Kr(5s) include the metastable 3P0,2 levels ‘as well as the two 3P1 levels, which are optically trapped’ (p. 14). The paper prints no ionisation energy of these averaged levels; Fig. 1 draws the levels against an energy axis (eV) but prints no level energy as a number.

WHAT IS TAKEN (tools/extract/hyman_1977.py). Table I (p. 15), the cross sections at ‘lambda = 2486 A’ (the KrF laser, ‘5 eV’, p. 14; whether in air or vacuum is not said, a difference of 0.07 nm): Ar(4s) 2.1 x 10^-20, Ar(4p) 4.3 x 10^-18, Kr(5s) 1.3 x 10^-19, Kr(5p) 4.5 x 10^-18 cm2. The library’s cells are an OCR (‘4. 3x 10-18’), kept in ‘printed’. No uncertainty is stated; the paper expects the p-state values to be ‘relatively insensitive to the model and ... more accurate’, and the s-state values, near a zero of the matrix element, ‘very sensitive to the details of the model’ (p. 15). All are checks: a central-field model of configuration-averaged levels.

CHECKED (the script). The text repeats Table I’s Ar(4p) 4.3 x 10^-18 (p. 15) and the abstract’s ‘~4.5 x 10^-18’ for the p states. Figs. 2 and 3 read from the page images (record of the method in the script): Table I’s Ar(4p) value lies on Fig. 2’s curve at epsilon = 0.167 Ry and Kr(5p)’s on Fig. 3’s at 0.170 Ry, so with the photon energy of 2486 A (0.3667 Ry of 13.6 eV) the calculation’s binding energies are 2.72 eV (Ar 4p) and 2.68 eV (Kr 5p) (+- 0.03 eV from the reading, see the register). The traced curves, drawn back on the page images, were inspected (overlays).

COMPARISONS. dakka_2018 (Table I, ‘Literature’) quotes sigma_ei = 3.3 x 10^-18 cm2 for Kr 2p6 (4p5 5p[3/2]2) at 215 nm, ‘Calculated from’ this paper: Fig. 3’s 5p curve, read 0.0573 Ry (the photon-energy difference between 215 nm and 2486 A) above the point where it has Table I’s value, gives 3.39 x 10^-18 cm2, so the quotation is this calculation’s configuration average carried to 215 nm along Fig. 3 (agreement 3 %, within the reading). chang_1982 (Table II) prints the later Duzy and Hyman values (Phys. Rev. A 22, 1978 (1980), as printed there) at 248 nm, 5.4 (Ar 4p) and 5.2 (Kr 5p) Mb, 26 and 16 % above this paper’s 4.3 and 4.5 at 248.6 nm; its own length-form 4.8 and 4.5 Mb at 248 nm are, as it says, closer to this paper’s than to Duzy and Hyman’s. chang_1982’s calculated binding energies (Ry / n*^2: Ar 4p 2.56, Kr 5p 2.42 eV) are below the 2.72 and 2.68 eV implied here.

NOT TAKEN. Figs. 2 and 3 (pp. 14-15), sigma of the 4s and 4p (Ar) and 5s and 5p (Kr) states against the photoelectron’s excess energy epsilon from 0 to 1 Ry, raster scans: the quantity is held against the photon’s wavelength, and the photon energy of a point needs the level’s ionisation energy, which is printed nowhere (it could only be read off Fig. 1’s drawing, a second raster reading under every abscissa). Dunning and Stebbings’s threshold upper bounds for Ar(4s 3P0,2), 1.1 x 10^-18, and Kr(5s 3P0,2), 4.9 x 10^-19 cm2 (F. B. Dunning and R. F. Stebbings, Phys. Rev. A 9, 2378 (1974); bounds at an unstated photon energy, not in the library). The Ar(4s) value renormalised to that bound, ‘~1.5 x 10^-19 cm2’ at 2486 A (p. 15): a rescaling, not a calculation.

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

Datasets#

hyman_1977/table1_4s#

{
  "id": "table1_4s",
  "material": "Ar",
  "file": "Ar/hyman_1977__table1_4s.csv",
  "table": "tbl_ae5d166a6610",
  "quantity": "excited_state_photoionization_cross_section",
  "unit": "cm2",
  "abscissa_unit": "angstrom",
  "use": "check",
  "parameters": {
    "initial_level": "Ar 3p5 4s, averaged over J and the core state (the 3P0,2 metastable levels and 'the two 3P1 levels', p. 14)",
    "method": "central-field model (Hartree-Fock ion potential plus a polarisation potential), no spin-orbit"
  }
}

Table I (p. 15), Ar(4s) at 2486 A: 2.1 x 10^-20 cm2. No uncertainty is stated; the s-state values are ‘very sensitive to the details of the model’ (p. 15).

hyman_1977/table1_4p#

{
  "id": "table1_4p",
  "material": "Ar",
  "file": "Ar/hyman_1977__table1_4p.csv",
  "table": "tbl_ae5d166a6610",
  "quantity": "excited_state_photoionization_cross_section",
  "unit": "cm2",
  "abscissa_unit": "angstrom",
  "use": "check",
  "parameters": {
    "initial_level": "Ar 3p5 4p, averaged over J and the core state",
    "method": "central-field model (Hartree-Fock ion potential plus a polarisation potential), no spin-orbit"
  }
}

Table I (p. 15), Ar(4p) at 2486 A: 4.3 x 10^-18 cm2 (repeated on p. 15). No uncertainty is stated.

hyman_1977/table1_5s#

{
  "id": "table1_5s",
  "material": "Kr",
  "file": "Kr/hyman_1977__table1_5s.csv",
  "table": "tbl_ae5d166a6610",
  "quantity": "excited_state_photoionization_cross_section",
  "unit": "cm2",
  "abscissa_unit": "angstrom",
  "use": "check",
  "parameters": {
    "initial_level": "Kr 4p5 5s, averaged over J and the core state (the 3P0,2 metastable levels and 'the two 3P1 levels', p. 14)",
    "method": "central-field model (Hartree-Fock ion potential plus a polarisation potential), no spin-orbit"
  }
}

Table I (p. 15), Kr(5s) at 2486 A: 1.3 x 10^-19 cm2. No uncertainty is stated; the s-state values are ‘very sensitive to the details of the model’ (p. 15).

hyman_1977/table1_5p#

{
  "id": "table1_5p",
  "material": "Kr",
  "file": "Kr/hyman_1977__table1_5p.csv",
  "table": "tbl_ae5d166a6610",
  "quantity": "excited_state_photoionization_cross_section",
  "unit": "cm2",
  "abscissa_unit": "angstrom",
  "use": "check",
  "parameters": {
    "initial_level": "Kr 4p5 5p, averaged over J and the core state",
    "method": "central-field model (Hartree-Fock ion potential plus a polarisation potential), no spin-orbit"
  }
}

Table I (p. 15), Kr(5p) at 2486 A: 4.5 x 10^-18 cm2 (the abstract’s ‘~4.5 x 10^-18’ for the p states). No uncertainty is 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.