crance_1985

M. Crance and M. Aymar, “Two-photon detachment of H-. A model calculation”, J. Phys. B: At. Mol. Phys. 18, 3529-3536 (1985)

Source record · Catalogue · Review register

DOI: 10.1088/0022-3700/18/17/014

Source kind: theory

Recorded technique: One- and two-photon detachment of the H- ground state in the dressed-atom picture (atom plus quantised field, Eqs. 1-5), linear polarisation, dipole approximation, a real Hamiltonian in a basis of complex square-integrable two-electron functions (Eq. 6, (lambda r e^(-i theta))^(l+n) exp(-lambda r e^(-i theta)/2), several theta in 0-pi/2: the complex-basis equivalent of complex scaling). The complex energy of the perturbed ground state is followed with the field; its imaginary part gives the detachment probability, sigma^(1) = 2 Im(E_g) / hbar I (Eq. 16) and sigma^(2) = 2 Im(E_g) / hbar I^2 (Eq. 18), the basis restricted to the multiplicities that give Im(E_g) to fourth order in the field (lowest-order perturbation theory in the field, configuration interaction treated non-perturbatively). Ground state: ss’, pp’, dd’ 1S configurations (n_s = 6, n_p = n_d = 5), E_g = -0.5273 au against Pekeris’s -0.5277 (Table 1). Two-photon final states 1S and 1D (ss’, p2, d2, sd’), between the three-photon and one-photon detachment thresholds, E_A/2 < hbar omega < E_A (Eq. 17); ‘about 15% for two-photon processes’ from enlarging the basis (p. 3534).

Materials in structured entries: None recorded.

Dataset quantities: None recorded.

Contents: 0 datasets; 0 formulas.

Curation notes

J. Phys. B: At. Mol. Phys. 18, 3529-3536 (1985) = PDF pages 2-9 (PDF page 1 is the IOPscience cover sheet; journal page = PDF page + 3527). Identity checked on PDF pages 1-2 (the cover: ‘1985 J. Phys. B: At. Mol. Phys. 18 3529’; the title page: Michele Crance and Mireille Aymar, Laboratoire Aime Cotton, Orsay; received 4 February 1985) on 2026-10-09. The pages are scanned images (2076 x 2945 pixels) with a text layer.

NOTHING TAKEN. The paper is about the negative hydrogen ion, H-, which the material registry does not hold (no anion is registered; ‘ion’ is a gas-phase cation, TC-440), and the vocabulary’s quantities are for the neutral gases and their cations. Its numbers: Table 1 (p. 3533), ground-state expectation values of H- (E_g, <r_1>, <r_1^2>, <r_12^2> in au; this work -0.5273, 2.70, 11.66, 24.7 against Pekeris -0.5277, 2.71, 11.91, 25.2; checked against the table image), no quantity; Fig. 1 (p. 3534), the one-photon detachment cross section of H- for 0.03 < omega < 0.10 au against Smith and Burch’s measurements and Chandrasekhar’s and Broad and Reinhardt’s calculations (raster); Fig. 2 (p. 3535), log-log, the two-photon detachment cross sections sigma_s^(2), sigma_d^(2) (final 1S and 1D) and their total, in s^-1 (W cm^-2)^-2, against the photoelectron energy epsilon = 2 hbar omega - E_A (Eq. 20) in cm^-1 (about 70 to 3500 cm^-1), 1e-13 to 1e-10 (raster; the abstract: ‘between 0 and 10^-10 s^-1 (W cm^-2)^-2’); near threshold sigma_s ~ epsilon^(1/2) and sigma_d ~ epsilon^(5/2) (O’Malley’s threshold law, drawn as dashed lines), sigma_s largest near omega = 0.019 au (p. 3535).

WHY IT IS HERE. It is cited among the two-photon references of the curated records: pan_1990b (TC-908; its Ref. 16, with Fink and Zoller, for the negative hydrogen ion, p. 6271) and starace_1987 (TC-878; its Ref. 19), both listed under ‘H-’ in those records’ notes, and nikolopoulos_2001 (below). bachau_1990 (TC-905) does not cite it (its Ref. 6 is Crance’s chapter in Chin and Lambropoulos’s book). It is a method reference: two-photon detachment of a two-electron system by a dressed-atom complex-basis calculation, an L^2 basis with complex exponents only for the continua that carry a pole and real functions elsewhere (Sec. 2.2, pp. 3531-3532).

FINDING (a citation elsewhere): nikolopoulos_2001 (TC-875, its notes) quotes ‘Crance and Aymar, J. Phys. B 18, 3529 (1985)’ for two-photon DOUBLE ionisation cross sections of helium, 2.05, 1.74 and 1.73 x 10^-55 cm4 s at 43.5, 45 and 46.25 eV, as Nikolopoulos and Lambropoulos’s paper prints that reference (its p. 559 and reference list). This paper, at that volume and page, is the H- detachment calculation above: it contains no helium values and no double ionisation. The helium values’ true source is not identified here.

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

Datasets

No datasets are recorded.

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.