hyatt_1973#
H. A. Hyatt, J. M. Cherlow, W. R. Fenner and S. P. S. Porto, “Cross section for the Raman effect in molecular nitrogen gas”, J. Opt. Soc. Am. 63, 1604 (1973)
Source record · Catalogue · Review register
Source kind: measurement
Recorded technique: The N2 Q-branch (2331 cm-1) Raman intensity compared with that of the H2 J = 1 -> 3 pure rotational line, whose absolute cross section is computed from theory (Placzek’s polarizability theory with Ford and Browne’s tables of the H2 anisotropy): Eq. (8), (dsigma(N2)/dOmega)_Q = Phi(J) (dsigma(H2)/dOmega)_J I_Q(N2)/I_J(H2). Plane-polarized 488.0 and 514.5 nm argon-ion light (about 900 mW, single pass), right-angle geometry with the laser polarized perpendicular to the scattering plane, gases at 1 atm and 22 C, collection solid angle about 0.15 sr, Spex 1400 double monochromator with an S-20 photomultiplier (dc detection), response calibrated against an NBS quartz-iodine lamp, scattered light analysed with a Polaroid sheet, wide slits (peak heights of the trapezoidal lines taken as proportional to the intensities) (pp. 1604-1605). The relative N2 cross section was also measured at six laser wavelengths (Fig. 1).
Materials in structured entries: H2, N2
Dataset quantities: raman_cross_section
Contents: 4 datasets; 0 formulas.
Curation notes#
Journal pages 1604-1606 = PDF pages 1-3 (page n of the PDF is p. 1603 + n). Identity checked on the first page (the library’s identity carries warnings only because the PDF prints no DOI). Received 4 June 1973. The same group’s earlier paper is fenner_1973 (ref. 9 here).
TABLE I (p. 1605, ‘Theoretical Raman cross section for the J = 1 -> 3 pure rotational transition in molecular hydrogen gas at temperature 22 C’; the CSV matches the image): per laser wavelength, sigma_0 (the total cross section, cm2/mol), dsigma(H2)/dOmega (cm2/mol sr, at theta = 90 deg to the incident polarization) and Phi(1) dsigma/dOmega (cm2/mol sr, per molecule of the gas at 22 C). The dsigma/dOmega column is the dataset theory_S1_H2 (use = “check”: a calculation, from Ford and Browne’s tables, ref. 16 = ford_1973, Phys. Rev. A 7, 418 (1973), curated, and ref. 17, Atomic Data 5, 305 (1973), not in the library; ‘the communication of computational results before publication by A. L. Ford and J. C. Browne’ is acknowledged, p. 1606). The other columns (quoted, not stored: sigma_0 is a total cross section, and Phi(1) dsigma/dOmega is per molecule of normal H2, not per molecule in J = 1): 488.0 nm: sigma_0 2.69 x 10^-29, Phi(1) dsigma/dOmega 1.48 x 10^-30; 514.5 nm: 2.14 x 10^-29 and 1.18 x 10^-30. The theory (pp. 1604-1605): Eq. (1), [dsigma/dOmega]_J = (3/8 pi) sigma_0(J) (6 + sin^2 theta)/10, theta the angle of observation to the electric vector; Eq. (2), sigma_0(J) = (128 pi^5/(9 lambda_R^4)) S(J) gamma_00^2, lambda_R the Raman wavelength, gamma_00 the anisotropy of the v = 0 level; Eq. (3), S(J) = (J+1)(J+2)/((2J+3)(2J+1)) for Stokes lines; rho_L = 3/4. ‘d sigma/d Omega = 21 sigma_0(1)/80 pi’ at 90 deg; Phi(1) = 0.6601 (Eq. 6, normal H2 at 22 C, term values from Herzberg’s constants). Checked (2026-09-27): 21 sigma_0/(80 pi) = 2.248 x 10^-30 (488.0) and 1.788 x 10^-30 (514.5), against the printed 2.25 and 1.79; 0.6601 x the printed column = 1.485 and 1.182, against 1.48 and 1.18. ‘mol’ is molecule.
MISPRINT (Table I, 514.5 nm, dsigma/dOmega): the page prints ‘1.79 x 19^-30’ (image checked); the power is 10^-30, as the check above and the other cells show. The mantissa 1.79 is the value, at the dataset’s scale 1e-30 (the raw cell stays in the printed column; see tools/extract/hyatt_1973.py). No erratum is needed: no stored number changes.
TABLE II (p. 1605, ‘Absolute differential Raman cross section of the 2331-cm-1 Q-branch Raman transition in N2 gas. All cross sections in units of cm2/mol sr’; JSON cells match the image): ‘This work’ (5.4 +- 0.3) x 10^-31 at 488.0 nm and (4.2 +- 0.2) x 10^-31 at 514.5 nm (dataset absolute_N2, primary; the +- level is not stated). The other rows are reproduced: Fenner et al. (ref. 9 = fenner_1973) 4.3 (against benzene, ‘c’) and 3.3 +- 1.1 (calibrated spectrometer, ‘d’) at 488.0 nm, identical to fenner_1973’s Table IV (dataset absolute_N2_fenner); Penney et al. (ref. 7) 4.4 +- 0.2 and Fouche and Chang (ref. 8) 4.4 +- 1.7 at 514.5 nm; Murphy et al. (ref. 6 = murphy_1969) 5.5 +- 0.4 and 4.4 +- 0.3, Stansbury et al. (ref. 5) 4.8 and 3.8, both ‘Prelaser results corrected to laser wavelengths by factor of nu_R^4’ (notes e-g) (dataset absolute_N2_others). ‘Our results are in good agreement with values obtained by different techniques. We feel that our experimental method is less subject to error than previous approaches’ (p. 1606).
GEOMETRY of the N2 value: right angle, the laser polarized perpendicular to the scattering plane, observed at 90 deg to the beam and to the electric vector (p. 1605). The paper does not say which scattered polarization the ratio I_Q/I_J uses; Eq. (1) is Placzek’s cross section summed over the scattered polarizations, and the N2 Q branch is nearly polarized (‘the depolarization ratio of nitrogen is so low’, p. 1605). The O- and S-branch lines of the N2 band ‘merge to give an apparent baseline’ and are judged negligible (p. 1605).
EXCITATION WAVELENGTHS: 488.0 and 514.5 nm, the argon-ion lines, recorded as standard air (not stated; the air-vacuum difference changes nu^4 by 0.1 %).
FIGURE 1 (p. 1606): the relative N2 Q-branch cross section at six laser wavelengths against nu_R^4 (the Raman wavenumber to the fourth), with a straight-line fit: ‘Within the experimental error, the measured frequency dependence of scattering follows the fourth power of the Raman frequency, as expected because, in nitrogen, no resonance effect is expected at visible wavelengths’. Figure only: not digitized. Check: 5.4/4.2 = 1.286 against ((20492 - 2331)/(19436 - 2331))^4 = 1.271 (vacuum wavenumbers of the two lines), within the +-0.3 and +-0.2.
REPRODUCTIONS ELSEWHERE: danichkin_1981 Table 2 cites this paper as ref. [42]: (5.4 +- 0.3) x 10^-31 at 488.0 nm and (4.2 +- 0.2) x 10^-31 at 514.5 nm (the latter printed with its opening parenthesis missing), converted by Danichkin et al. to 5.5 and 5.4 at 488 nm. Danichkin’s row text ‘against the H2 rotational line 1-3’ matches this paper’s method.
Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.
Datasets#
hyatt_1973/theory_S1_H2#
{
"id": "theory_S1_H2",
"material": "H2",
"file": "H2/hyatt_1973__theory_S1_H2.csv",
"table": "tbl_fa72308ac503",
"quantity": "raman_cross_section",
"unit": "cm2/sr",
"scale": 1e-30,
"abscissa_unit": "nm",
"wavelength_medium": "standard_air",
"use": "check",
"parameters": {
"transition": "v=0 J=1 -> 3, S(1) pure rotational",
"geometry": "90 deg to the incident electric vector, both scattered polarizations"
}
}
Table I (p. 1605), dsigma(H2)/dOmega of the J = 1 -> 3 pure rotational (S(1)) line at theta = 90 deg to the incident polarization, both scattered polarizations (Eq. 1, 21 sigma_0/(80 pi)), per molecule in J = 1, computed from Ford and Browne’s anisotropy tables (refs. 16 = ford_1973 and 17) at 22 C. A calculation, not a measurement; no uncertainty stated. The 514.5 nm cell’s power is misprinted 19^-30 (see the record’s notes).
hyatt_1973/absolute_N2#
{
"id": "absolute_N2",
"material": "N2",
"file": "N2/hyatt_1973__absolute_N2.csv",
"table": "tbl_e6410a8fb5ef",
"quantity": "raman_cross_section",
"unit": "cm2/sr",
"scale": 1e-31,
"abscissa_unit": "nm",
"wavelength_medium": "standard_air",
"use": "primary",
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "v=0-1 Q branch (2331 cm-1)",
"geometry": "90 deg to the beam and to the incident electric vector"
}
}
Table II (p. 1605), ‘This work’: the N2 Q-branch (2331 cm-1) differential cross section, cm2/mol sr (per molecule), from Eq. (8) against the theoretical H2 S(1) cross section (theory_S1_H2), gases at 1 atm and 22 C. The +- is as printed; its level is not stated. Scattered polarization: see the record’s notes.
hyatt_1973/absolute_N2_fenner#
{
"id": "absolute_N2_fenner",
"material": "N2",
"file": "N2/hyatt_1973__absolute_N2_fenner.csv",
"table": "tbl_e6410a8fb5ef",
"quantity": "raman_cross_section",
"unit": "cm2/sr",
"scale": 1e-31,
"abscissa_unit": "nm",
"wavelength_medium": "standard_air",
"use": "reproduced",
"reproduced_from": [
"fenner_1973"
],
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "v=0-1 Q branch (2331 cm-1)"
}
}
Table II (p. 1605), the two Fenner et al. rows (ref. 9, notes c: ‘Comparison with liquid-benzene cross section of Kato and Takuma’, d: ‘Calibrated spectrometer’): identical to fenner_1973’s Table IV (absolute_N2_benzene 4.3 and absolute_N2 3.3 +- 1.1).
hyatt_1973/absolute_N2_others#
{
"id": "absolute_N2_others",
"material": "N2",
"file": "N2/hyatt_1973__absolute_N2_others.csv",
"table": "tbl_e6410a8fb5ef",
"quantity": "raman_cross_section",
"unit": "cm2/sr",
"scale": 1e-31,
"abscissa_unit": "nm",
"wavelength_medium": "standard_air",
"use": "reproduced",
"reproduced_from": [
"C. M. Penny [sic], L. M. Goldman, M. Lapp, Nat. Phys. Sci. 235, 110 (1972)",
"D. G. Fouche and R. K. Chang, Appl. Phys. Lett. 20, 256 (1972)",
"murphy_1969",
"E. J. Stansbury, M. F. Crawford, and H. L. Welsh, Can. J. Phys. 31, 954 (1953)"
],
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "v=0-1 Q branch (2331 cm-1)"
}
}
Table II (p. 1605), the other rows: Penney et al. (note a: ‘Calibrated spectrometer and comparison with Rayleigh scattering’) and Fouche and Chang (note b: ‘Comparison with liquid-benzene cross section of Skinner and Nilsen’) at 514.5 nm; Murphy et al. (notes e, f: comparison with methane) and Stansbury et al. (notes e, g: comparison with Rayleigh scattering) at both wavelengths, ‘Prelaser results corrected to laser wavelengths by factor of nu_R^4’ by Hyatt et al. The +- as printed, level 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.