russell_1987#
D. A. Russell and W. B. Roh, “High-resolution CARS measurement of Raman linewidths of deuterium”, J. Mol. Spectrosc. 124, 240 (1987)
Source record · Catalogue · Review register
DOI: 10.1016/0022-2852(87)90139-1
Source kind: measurement
Recorded technique: High-resolution cw CARS (p. 240): a single-mode Ar-ion pump at 514.5 nm (effective linewidth about 0.0003 cm-1, which limits the resolution) and a single-mode ring-dye Stokes beam at 608 nm, collinear, focused into a cell of D2; anti-Stokes detection by photon counting; frequency markers from an etalon, calibration with a wavemeter and an iodine cell. D2 Q(0)-Q(4) of the fundamental band at room temperature, 0.3-18 amagat (Q(4) below 10 amagat); each point the average of three measurements. Linewidth against density fitted with the Dicke (diffusion) law, Eq. (1), by linear least squares for a and D_0.
Materials in structured entries: D2
Dataset quantities: raman_linewidth
Contents: 3 datasets; 1 formula.
Curation notes#
Identity checked against the first page. Page numbers are journal pages (pdf pages 1-3 = pp. 240-242). Material: D2 as supplied (normal, ortho:para not stated; at room temperature). ‘room temperature’ is the only temperature given (Fig. 1 caption, p. 241); no value in K. 1 amagat ‘is equal to the number density of gas at 1 atm at 273 K’ (p. 240).
WIDTH CONVENTION. FULL widths. Eq. (1), p. 240: ‘Delta nu = (4 pi nu^2/c)(D_0/rho) + a rho, where Delta nu is the linewidth (FWHM in cm-1), nu is the frequency of the vibrational Raman transition (in cm-1), rho is the gas density (in amagat), c is the speed of light (in cm/sec), a is the pressure broadening coefficient (in cm-1/amagat), and D_0 is the self-diffusion coefficient at 1 amagat.’ Table I note: ‘a in [10^-3 cm-1/amagat]; D_0 in [cm2-amagat/sec]; delta: rms error of the fit in [10^-3 cm-1]’. The law INCLUDES the Dicke term, (4 pi nu^2/c) D_0/rho (FWHM, cm-1), fitted (D_0 per J, formula eq1_dicke). Independent confirmation of FWHM: Smyth et al. (smyth_1987, Table III, HWHM) print ‘Roh (Ref. 33)’ values 2.90 +- 0.04, 1.32 +- 0.02, 1.96 +- 0.02, 2.06 +- 0.04, 1.94 +- 0.04 for Q(0)-Q(4), which are this table’s a and errors halved and rounded (5.79/2 = 2.895, 2.63/2 = 1.315, 3.91/2 = 1.955, 4.11/2 = 2.055, 3.87/2 = 1.935).
UNCERTAINTIES. The +- on a and D_0 are the least-squares fit errors (‘the fitting errors for the present measurement are more than five times smaller than those associated with Murray and Javan’s measurements’, p. 241); level not stated. delta, the rms error of the fit (10^-3 cm-1): 0.6, 1.2, 1.1, 1.1, 0.8 for Q(0)-Q(4). Q(4) is ‘somewhat less reliable’ (smaller density range, poor S/N, p. 241).
THE COMPARISON COLUMNS (p. 241, reproduced). Murray and Javan (J. R. Murray and A. Javan, J. Mol. Spectrosc. 42, 1 (1972), curated as murray_1972 since 2026-09-27; it calls its widths full widths): a = 1.4 +- 0.15, 2.2 +- 0.2, 2.6 +- 0.5 (Q(1)-Q(3)), D_0 = 0.952 for each, delta 7, 7, 8. The paper says ‘the present pressure-broadening coefficients deviate almost 100 % from those of Murray and Javan’ and blames Murray and Javan’s 0.053 cm-1 instrument width. But Smyth et al. 1987 (smyth_1987 Table III, ‘half-width at half-maximum’) print the same three numbers, 1.4 +- 0.15, 2.2 +- 0.2, 2.6 +- 0.5, as HWHM, in agreement with their own HWHM (1.33, 2.06, 2.13): the ‘almost 100 %’ deviation is the factor of 2 between a half width and a full width. The original (murray_1972) says its widths are FWHM, so they are recorded as ‘fwhm’ (the original’s word; this paper tabulates them under its FWHM a too, and Smyth et al. call them HWHM): the factor of 2 is then between Murray and Javan’s D2 widths and every later D2 measurement, unresolved (murray_1972’s notes). Robertson and Hunt (C. W. Robertson and R. H. Hunt, J. Chem. Phys. 55, 4149 (1971); electric-field-induced infrared absorption at 10-30 amagat, no D_0): 5.77 +- 0.2, 2.59 +- 0.10, 4.00 +- 0.10, 4.22 +- 0.10, 4.14 +- 0.15, within 3 % of this study for Q(0)-Q(3) (p. 240); smyth_1987 prints exactly half of them as HWHM (2.89 +- 0.10, 1.30 +- 0.05, 2.00 +- 0.05, 2.11 +- 0.05, 2.07 +- 0.08), so Robertson and Hunt’s are FWHM, consistent with this table.
NOTE ADDED IN PROOF (p. 242): Rosasco’s group’s stimulated Raman gain widths ‘appear to be in agreement with ours within approximately 6 %’ (smyth_1987).
What this bears on: the D2 Q-branch width law in use is Ottusch and Rockwell’s, FWHM = 101/rho + 120 rho MHz (rho in amagat) for Q(2), cited to this paper and to smyth_1987 (ottusch_1988 linewidth_D2). Its 101 MHz amagat is this paper’s Q(2) Dicke term, (4 pi nu^2/c) D_0 with D_0 = 0.901 and nu = 2987 cm-1 (Hanna et al.’s Q(2) shift): 3.370e-3 cm-1 amagat = 101.0 MHz amagat. Its 120 MHz/amagat is the mean of this paper’s a(Q(2)) = 3.91e-3 cm-1/amagat = 117.2 MHz/amagat and smyth_1987’s 2 x 2.06e-3 = 123.5 MHz/amagat (mean 120.4): an inference from the numbers, not stated by Ottusch and Rockwell.
Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.
Datasets#
russell_1987/table1_a#
{
"id": "table1_a",
"material": "D2",
"file": "D2/russell_1987__table1_a.csv",
"table": "tbl_99029db61edc",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "primary",
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "fwhm",
"perturber": "self"
}
}
Table I (p. 241), ‘This Study’, a: the FWHM pressure-broadening coefficient of Eq. (1) (Dicke term fitted separately) of the D2 Q(0)-Q(4) lines (v = 0 -> 1), 10^-3 cm-1 per amagat, room temperature (no value in K). The +- is the fit error (level not stated). smyth_1987 quotes these halved as HWHM (‘Roh (Ref. 33)’).
russell_1987/table1_murray_javan_a#
{
"id": "table1_murray_javan_a",
"material": "D2",
"file": "D2/russell_1987__table1_murray_javan_a.csv",
"table": "tbl_99029db61edc",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "reproduced",
"reproduced_from": [
"murray_1972"
],
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "fwhm",
"perturber": "self"
}
}
Table I (p. 241), ‘Murray & Javan’, a, Q(1)-Q(3) (Q(0), Q(4) printed ‘-’); spontaneous Raman with a 0.053 cm-1 instrument width (p. 241). Tabulated under this paper’s FWHM a, but smyth_1987 (Table III) prints the same values as HWHM, and the ‘almost 100 %’ disagreement the paper reports is that factor of 2. Their D_0 is 0.952 for every line. Re-pointed to murray_1972 (2026-09-27): its Table II prints D2 Q_1(1)-Q_1(3) 1.4 +- 0.15, 2.2 +- 0.2, 2.6 +- 0.5 x 10^-3 cm-1/amagat at 25 C (digit-identical, with delta 7, 7, 8 and D_0 = 0.952 from its p. 16), and calls all its widths FULL widths (‘full width at half maximum’, its pp. 2 and 7; its Fig. 5 marks the FWHM Doppler widths): width is now ‘fwhm’, the original’s convention (was ‘not stated’). The factor-of-2 disagreement with this paper and with smyth_1987 (which reads them as HWHM) is therefore unresolved: murray_1972’s H2 widths agree with later FWHM measurements, its D2 widths with later HWHM ones (see murray_1972’s DOUBT).
russell_1987/table1_robertson_hunt_a#
{
"id": "table1_robertson_hunt_a",
"material": "D2",
"file": "D2/russell_1987__table1_robertson_hunt_a.csv",
"table": "tbl_99029db61edc",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "reproduced",
"reproduced_from": [
"C. W. Robertson and R. H. Hunt, J. Chem. Phys. 55, 4149 (1971)"
],
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "fwhm",
"perturber": "self"
}
}
Table I (p. 241), ‘Robertson & Hunt’, a, Q(0)-Q(4): electric-field-induced infrared absorption at 10-30 amagat (no D_0, no fit error reported, p. 240). FWHM, as this table’s a; smyth_1987 prints exactly half of each (Robertson, Hunt and Brannon, same reference) as HWHM.
Formulas#
russell_1987/eq1_dicke#
{
"id": "eq1_dicke",
"material": "D2",
"equation": "Eq. (1), p. 240; Table I (tbl_99029db61edc), p. 241",
"printed": "Delta nu = (4 pi nu^2 / c) (D_0 / rho) + a rho",
"variable": "Delta nu: the linewidth, FWHM in cm-1; nu: the frequency of the Q(J) transition in cm-1 (not printed in the paper); rho: density in amagat; c in cm/s; D_0: self-diffusion coefficient at 1 amagat in cm2 amagat/s; a: pressure-broadening coefficient in cm-1/amagat (Table I in 10^-3 cm-1/amagat, dataset table1_a)",
"state": "pure D2, room temperature",
"density": "unknown",
"range": "0.3-18 amagat (Q(4) below 10 amagat)",
"coefficients": {
"a_Q0": "5.79",
"a_Q0_error": "0.08",
"D0_Q0": "1.084",
"D0_Q0_error": "0.13",
"a_Q1": "2.63",
"a_Q1_error": "0.04",
"D0_Q1": "0.873",
"D0_Q1_error": "0.09",
"a_Q2": "3.91",
"a_Q2_error": "0.04",
"D0_Q2": "0.901",
"D0_Q2_error": "0.06",
"a_Q3": "4.11",
"a_Q3_error": "0.08",
"D0_Q3": "1.083",
"D0_Q3_error": "0.13",
"a_Q4": "3.87",
"a_Q4_error": "0.08",
"D0_Q4": "0.913",
"D0_Q4_error": "0.20"
},
"check": "No width is printed to reproduce (Fig. 1 is a figure). Checked (scratch, 2026-09-27) against ottusch_1988's D2 Q(2) law: the Dicke term (4 pi nu^2/c) D_0 with D_0 = 0.901 and nu = 2987 cm-1 (hanna_1986's Q(2) shift) is 3.370e-3 cm-1 amagat = 101.0 MHz amagat, Ottusch and Rockwell's 101. The paper's D_0 are 'J dependent' (0.87-1.08); smyth_1987 finds no J dependence (0.984 and 0.967 cm2/s for Q(1), Q(2) at 298.5 K)."
}
The a_ coefficients are as printed, in 10^-3 cm-1/amagat (multiply by 1e-3 for Eq. (1) in cm-1). The D_0 of Table I; Murray and Javan’s D_0 = 0.952 (all lines) is in the source notes. The paper’s comparison: ‘the agreement between the present results and the infrared data is excellent, being within 3 % of each other for the Q(0)-Q(3) lines’ (p. 240).
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.