lu_1987#

Z. Lu and D. P. Shelton, J. Chem. Phys. 87, 1967 (1987)

Source record · Catalogue · Review register

Source kind: measurement

Recorded technique: ESHG with periodic phase matching of CF4 against N2 at seven visible wavelengths (488.0-659.8 nm), with the phase-match density ratio as a by-product; perturbation-theory expressions for the vibrational hyperpolarizability of a tetrahedral molecule, evaluated with infrared and Raman matrix elements (pp. 1967-1970).

Materials in structured entries: None recorded.

Dataset quantities: None recorded.

Contents: 0 datasets; 0 formulas.

Curation notes#

CF4 is not a curated species: no dataset is taken. The paper contains, for CF4 only: Table I, gamma_CF4/gamma_N2 and gamma_CF4 (1e-63 C^4 m^4 J^-3; calibrated with Mizrahi & Shelton’s gamma_N2/gamma_He (ref 18, mizrahi_1985_arn2o2) and Sitz & Yaris’s ab initio gamma_He (ref 25) as in shelton_1986_ch4 (ref 26)) and the linear dispersion ratio Delta alpha_CF4/Delta alpha_N2 at 659.8-488.0 nm; Table II, earlier CF4 values (dc Kerr, ESHG, THG, reproduced); Table III, CF4 infrared and Raman transition matrix elements; the vibrational gamma for ESHG and the dc Kerr effect (Eqs. 18, 22, 23; gamma^v_Kerr = 23.0e-63 C^4 m^4 J^-3, Eq. 31), and alpha^v(0) = 1.12e-40 C^2 m^2 J^-1. The conclusion for CF4: ‘gamma^v/gamma^e ~ 1%, 10%, and 30% for THG, ESHG, and the dc Kerr effect’ (p. 1975).

Relevant to curated gases, from the text only (p. 1974): with Buckingham and Stephen’s theoretical hyper-Rayleigh |beta_xyz| ~ 7.8e-52 C^3 m^3 J^-2 for CH4 and the transition matrix elements of Elliott & Ward (ref 8), ‘one obtains from Eq. (18) the estimate gamma^v_ESHG = 3 x 10^-63 C^4 m^4 J^-3 for CH4. This is only 1% of the total gamma_ESHG of CH4’ (at optical frequencies, where gamma^v_ESHG is nearly frequency independent; no wavelength is given, so it is not made a dataset; shelton_1990 cites it, ref 45 and this paper). Also (p. 1975): Elliott & Ward’s calculation ‘gave gamma^v_Kerr ~ 3 gamma^e, which is about 10x too large (note that an extra factor of 1/6 is included in the definition of gamma in Ref. 8)’: Elliott & Ward’s gamma is 1/6 of Shelton’s.

Corrections by the later paper (shelton_1988, p. 150): Eqs. (18) and (23) here ‘are incorrect by factors of 2 and 3’; the CF4 hyper-Raman beta is 2x the value reported here. Journal pages are the PDF page plus 1965 (the PDF’s first page is the publisher’s cover).

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.