smyth_1987#
K. C. Smyth, G. J. Rosasco and W. S. Hurst, “Measurement and rate law analysis of D2 Q-branch line broadening coefficients for collisions with D2, He, Ar, H2, and CH4”, J. Chem. Phys. 87, 1001 (1987)
Source record · Catalogue · Review register
DOI: 10.1063/1.453333
Source kind: measurement
Recorded technique: High-resolution cw stimulated Raman spectroscopy, amplitude- and phase-modulated (pp. 1002-1003): a single-mode Kr-ion pump at 676 nm (about 700 mW, < 15 MHz FWHM) and a ring-dye probe (about 1 MHz), copropagating through a multipass cell (10-40-fold), forward scattering; frequency differences to +-0.1e-3 cm-1 (3 MHz). D2 Q(0)-Q(5), v = 0 -> 1, at room temperature (296.0-298.5 K): pure D2 at 0.87-20.0 amagat; 5 % D2 in He and H2 at 0.93-5.56 amagat; 10 % D2 in CH4 and Ar at 0.66-5.55 amagat and 2.5 % D2 in Ar at 0.28-3.74 amagat (Q(3), Q(4) only). Widths against density fitted with the Dicke expression, Eq. (1); at 1-10 amagat each line fitted as a narrow major and a broad minor Lorentzian (‘two-line fits’), the narrow one’s width being used (pp. 1004-1006).
Materials in structured entries: D2
Dataset quantities: raman_linewidth
Contents: 13 datasets; 6 formulas.
Curation notes#
Identity checked against the first page. Page numbers are journal pages: the library pdf’s page 1 is the publisher’s cover sheet, and pdf pages 2-12 are pp. 1001-1011. Material: D2 as supplied (normal, room-temperature ortho:para; not stated otherwise). HD appears only in the discussion. The foreign partners He, Ar, H2 and CH4 are the perturber ids.
WIDTH CONVENTION. HALF widths, per amagat. Eq. (1), p. 1004: ‘Gamma (HWHM, cm-1) = D_0 k^2/2 pi c rho + rho gamma, where c is the speed of light and gamma is the density independent line broadening coefficient’, k = 2 pi nu_Raman (forward scattering), D_0 the diffusion coefficient at 1 amagat, rho in amagat. Table I caption (p. 1005): ‘Line broadening coefficients (HWHM, 10^-3 cm-1/amagat)’; Table III caption (p. 1008): ‘units of 10^-3 cm-1/amagat, half-width at half-maximum’; Fig. 2 (p. 1005): ‘Total linewidth measurements (half-width at half-maximum)’. The width law INCLUDES the Dicke term D_0 k^2/(2 pi c rho) (HWHM, cm-1 with D_0 in cm2/s at 1 amagat; formula eq1_dicke); gamma, the tabulated coefficient, excludes it.
UNCERTAINTIES. Table I caption: ‘estimated uncertainties are +-3 % for J = 0-4 and +-5 % for J = 5’; p. 1005: ‘A conservative estimate of the total uncertainty in the line broadening coefficients for Q(0)-Q(4) is +-3 % and for Q(5) is +-5 %, since a measurement was made at only one density for this transition’ (level not stated). The two-line fits lower the coefficients by about 3 % (D2:D2, D2:He 2.8 %, D2:H2 2.2 %) and 8-9 % (D2:CH4, D2:Ar) against single Lorentzians; lines measured at one or two densities were corrected by the same factor (pp. 1005-1006). The rms uncertainties of the sets (p. 1007): +-0.07 (D2), +-0.05 (He), +-0.09 (Ar), +-0.06 (H2), +-0.15 (CH4) x 10^-3 cm-1/amagat.
MIXTURES. The foreign-gas coefficients come from 2.5-10 % D2 mixtures; the paper does not say whether the D2:D2 share of the collisions (2.5-10 % of the density) was subtracted. D2:H2 Q(4) and Q(5) are enhanced by near-resonant rotational energy exchange with H2 (p. 1009) and are outside the Table II fit (J = 0-3).
DIFFUSION (text; no quantity). Pure D2 (p. 1005): effective D_0 = 0.984 +- 0.022 (Q(1)) and 0.967 +- 0.022 cm2/s (Q(2)) at 298.5 K and 1.0 amagat (mass diffusion 0.950, Ref. 61); no J dependence. D2:He and D2:H2: the mass diffusion value 1.16 cm2/s at 296 K (Ref. 62) was used, to within 2 %. D2:CH4 0.471 +- 0.02 and D2:Ar 0.438 +- 0.02 cm2/s at 298 K and 1.0 amagat (p. 1006; mass diffusion 0.487 and 0.530). Single-Lorentzian coefficients (p. 1005): Q(1) 1.36 and Q(2) 2.13 x 10^-3 cm-1/amagat, against 1.33 and 2.06 from the two-line fits.
THE RATE LAW (Eqs. (2)-(3), p. 1006; Table II, p. 1007): a modified exponential gap (MEG) law for the rotationally inelastic rates plus a J-independent vibrational dephasing term; one formula per mixture (table2_*), each with the fit without and with the dephasing term. f(T0/T) = 1 (all at room temperature). The printed rms deviations are reproduced to 0.01 (see the checks).
OTHER TEXT VALUES. Keijser et al.’s pure rotational S(J) self-broadening of D2 at 293 K, HWHM, J = 0-5 (dataset keijser_S_branch, reproduced from keijser_1974, p. 1008). The O1(4) line in pure D2: 2.50 x 10^-3 cm-1/amagat (dataset o_branch_O4, p. 1009), and the elastic reorientation contributions derived from it and from the S lines (0.38; 0.80, 1.01, 0.48, 0.29 for S(0)-S(3)): notes only, model-derived. The rotationally inelastic parts of Q(0), 2.46 (D2), 1.61 (D2:H2), 1.51 (D2:He), 1.12 (D2:Ar) x 10^-3 cm-1/amagat (pp. 1009), and Meier et al.’s rate-implied 9.6, 9.0, 4.2: notes only. The note added in proof: Blackmore, Green and Monchick’s ab initio D2:He widths agree to 5-10 % for J = 0-5, with vibrational dephasing 0.80-0.99 x 10^-3 cm-1/amagat for J = 0, 2, 4 (p. 1010).
What this bears on: the D2 Q-branch width in use (Ottusch and Rockwell’s law, TC-492; ottusch_1988 cites this paper and russell_1987): pure D2 Q(2), gamma = 2.06e-3 cm-1/ amagat HWHM, i.e. 4.12e-3 cm-1/amagat = 123.5 MHz/amagat FWHM, against Ottusch and Rockwell’s 120; the Dicke term from D_0 = 0.967 (Q(2)) and nu = 2987 cm-1 is 2 pi nu^2 D_0/c = 54.2 MHz amagat HWHM (108.4 FWHM), against their 101 (Russell and Roh’s). The foreign-gas coefficients (He, Ar, H2, CH4) are the only curated D2 Q-branch foreign broadening. Table III reads Murray and Javan’s D2 coefficients as half widths (see russell_1987); the original (murray_1972, curated 2026-09-27) calls its widths full widths, so the question is open again (murray_1972’s DOUBT).
Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.
Datasets#
smyth_1987/table1_self#
{
"id": "table1_self",
"material": "D2",
"file": "D2/smyth_1987__table1_self.csv",
"table": "tbl_bedfcf2a5c4b",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "primary",
"uncertainty": {
"relative": 0.03,
"relative_rows": {
"Q(5)": 0.05
},
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "hwhm",
"perturber": "self",
"temperature_range_k": "296.0-298.5"
}
}
Table I (p. 1005), D2:D2: HWHM self-broadening coefficient gamma of D2 Q(0)-Q(5) (v = 0 -> 1), 10^-3 cm-1 per amagat, room temperature (296.0-298.5 K), Dicke term excluded (Eq. (1)). +-3 % (J = 0-4), +-5 % (J = 5), a ‘conservative estimate of the total uncertainty’ (p. 1005). Q(5) from one density only. Table III repeats these with absolute errors (table3_this_work).
smyth_1987/table1_He#
{
"id": "table1_He",
"material": "D2",
"file": "D2/smyth_1987__table1_He.csv",
"table": "tbl_bedfcf2a5c4b",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "primary",
"uncertainty": {
"relative": 0.03,
"relative_rows": {
"Q(5)": 0.05
},
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "hwhm",
"perturber": "He",
"temperature_range_k": "296.0-298.5"
}
}
Table I (p. 1005), D2:He: HWHM broadening coefficient of D2 Q(0)-Q(5) by He, 10^-3 cm-1 per amagat of the mixture (5 % D2 in He, 0.93-5.56 amagat), room temperature (296.0-298.5 K); the D2:D2 share of the collisions not stated as removed. +-3 % (J = 0-4), +-5 % (J = 5).
smyth_1987/table1_Ar#
{
"id": "table1_Ar",
"material": "D2",
"file": "D2/smyth_1987__table1_Ar.csv",
"table": "tbl_bedfcf2a5c4b",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "primary",
"uncertainty": {
"relative": 0.03,
"relative_rows": {
"Q(5)": 0.05
},
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "hwhm",
"perturber": "Ar",
"temperature_range_k": "296.0-298.5"
}
}
Table I (p. 1005), D2:Ar: HWHM broadening coefficient of D2 Q(0)-Q(5) by Ar, 10^-3 cm-1 per amagat of the mixture (10 % D2 in Ar at 0.66-5.55 amagat, and 2.5 % at 0.28-3.74 amagat for Q(3), Q(4)), room temperature (296.0-298.5 K); the D2:D2 share not stated as removed. Q(0), Q(3)-Q(5) from one or two densities, corrected by the Q(1)-Q(2) two-line factor (8-9 %). +-3 % (J = 0-4), +-5 % (J = 5).
smyth_1987/table1_H2#
{
"id": "table1_H2",
"material": "D2",
"file": "D2/smyth_1987__table1_H2.csv",
"table": "tbl_bedfcf2a5c4b",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "primary",
"uncertainty": {
"relative": 0.03,
"relative_rows": {
"Q(5)": 0.05
},
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "hwhm",
"perturber": "H2",
"temperature_range_k": "296.0-298.5"
}
}
Table I (p. 1005), D2:H2: HWHM broadening coefficient of D2 Q(0)-Q(5) by H2 (normal), 10^-3 cm-1 per amagat of the mixture (5 % D2 in H2, 0.93-5.56 amagat), room temperature (296.0-298.5 K); the D2:D2 share not stated as removed. Q(4) and Q(5) are raised by near-resonant rotational energy exchange with H2 (p. 1009). +-3 % (J = 0-4), +-5 % (J = 5).
smyth_1987/table1_CH4#
{
"id": "table1_CH4",
"material": "D2",
"file": "D2/smyth_1987__table1_CH4.csv",
"table": "tbl_bedfcf2a5c4b",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "primary",
"uncertainty": {
"relative": 0.03,
"relative_rows": {
"Q(5)": 0.05
},
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "hwhm",
"perturber": "CH4",
"temperature_range_k": "296.0-298.5"
}
}
Table I (p. 1005), D2:CH4: HWHM broadening coefficient of D2 Q(0)-Q(5) by CH4, 10^-3 cm-1 per amagat of the mixture (10 % D2 in CH4, 0.66-5.55 amagat), room temperature (296.0-298.5 K); the D2:D2 share not stated as removed. Q(0), Q(3)-Q(5) from one or two densities, corrected by the two-line factor (8-9 %). +-3 % (J = 0-4), +-5 % (J = 5).
smyth_1987/table3_this_work#
{
"id": "table3_this_work",
"material": "D2",
"file": "D2/smyth_1987__table3_this_work.csv",
"table": "tbl_01b17bbca40c",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "check",
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "hwhm",
"perturber": "self",
"temperature_range_k": "296.0-298.5"
}
}
Table III (p. 1008), ‘This work’: Table I’s D2:D2 row repeated with absolute errors (3 %, and 5 % for Q(5), rounded). A duplicate of table1_self.
smyth_1987/table3_theory#
{
"id": "table3_theory",
"material": "D2",
"file": "D2/smyth_1987__table3_theory.csv",
"table": "tbl_01b17bbca40c",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "check",
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "hwhm",
"perturber": "self"
}
}
Table III (p. 1008), ‘Theory’ (note a): Robertson et al.’s (Ref. 31) calculated rotationally inelastic contribution with their adjustment of the D2 quadrupole moment removed, plus this paper’s vibrational dephasing estimate 0.51e-3 cm-1/amagat. A model, built from another paper’s calculation and this paper’s fit: a check, not a measurement. Q(0)-Q(4).
smyth_1987/table3_murray_javan#
{
"id": "table3_murray_javan",
"material": "D2",
"file": "D2/smyth_1987__table3_murray_javan.csv",
"table": "tbl_01b17bbca40c",
"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 III (p. 1008), ‘Murray and Javan (Ref. 10)’, Q(1)-Q(3), HWHM as the caption says. russell_1987 prints the same numbers under its FWHM a and calls them ‘almost 100 %’ below its own: the factor of 2 of a half against a full width. Agrees with this work within its errors. 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, but it calls its widths FULL widths (‘full width at half maximum’, its pp. 2 and 7; its Fig. 5 marks FWHM Doppler widths, and its H2 coefficients match later FWHM measurements). This table’s HWHM reading contradicts the original’s convention: width is now ‘fwhm’ (was ‘hwhm’), the original’s word. Numerically the values do match this paper’s HWHM (and are half of russell_1987’s FWHM): either Murray and Javan’s D2 widths are low by 2 or they are half widths despite their convention (unresolved; murray_1972’s DOUBT).
smyth_1987/table3_robertson#
{
"id": "table3_robertson",
"material": "D2",
"file": "D2/smyth_1987__table3_robertson.csv",
"table": "tbl_01b17bbca40c",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "reproduced",
"reproduced_from": [
"C. W. Robertson, R. H. Hunt and P. J. Brannon, J. Chem. Phys. 55, 4149 (1971)"
],
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "hwhm",
"perturber": "self"
}
}
Table III (p. 1008), ‘Robertson et al. (Ref. 31)’, Q(0)-Q(4), HWHM: exactly half of the values russell_1987 prints for ‘Robertson & Hunt’ as FWHM (5.77 -> 2.89, 2.59 -> 1.30, 4.00, 4.22 -> 2.11, 4.14 -> 2.07; errors halved).
smyth_1987/table3_gustafson_byer#
{
"id": "table3_gustafson_byer",
"material": "D2",
"file": "D2/smyth_1987__table3_gustafson_byer.csv",
"table": "tbl_01b17bbca40c",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "reproduced",
"reproduced_from": [
"E. K. Gustafson and R. L. Byer (personal communication), as cited in K. C. Smyth, G. J. Rosasco and W. S. Hurst, J. Chem. Phys. 87, 1001 (1987), Ref. 32"
],
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "hwhm",
"perturber": "self"
}
}
Table III (p. 1008), ‘Gustafson and Byer (Ref. 32)’, Q(0)-Q(4), HWHM (the caption); note b: ‘Uncertainty estimates not available’. Unpublished (personal communication); this is the only copy.
smyth_1987/table3_roh#
{
"id": "table3_roh",
"material": "D2",
"file": "D2/smyth_1987__table3_roh.csv",
"table": "tbl_01b17bbca40c",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "reproduced",
"reproduced_from": [
"russell_1987"
],
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "Q(J), v = 0 -> 1, per row",
"width": "hwhm",
"perturber": "self"
}
}
Table III (p. 1008), ‘Roh (Ref. 33)’ (‘W. B. Roh (personal communication, to be published)’), Q(0)-Q(4), HWHM: russell_1987’s Table I FWHM a halved and rounded (5.79 -> 2.90, 2.63 -> 1.32, 3.91 -> 1.96, 4.11 -> 2.06, 3.87 -> 1.94) with its errors halved (0.08 -> 0.04, 0.04 -> 0.02). Identified by the digits; Russell and Roh’s paper is the one published.
smyth_1987/keijser_S_branch#
{
"id": "keijser_S_branch",
"material": "D2",
"table": "text",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "reproduced",
"reproduced_from": [
"keijser_1974"
],
"parameters": {
"transition": "S0(J), v = 0, per row",
"width": "hwhm",
"perturber": "self",
"temperature_k": 293
}
}
6 inline points in the source record.
p. 1008: ‘Keijser et al. have measured line broadening coefficients for pure rotational S-branch transitions of 2.80, 2.23, 2.07, 1.70, 1.43, and 0.93 x 10^-3 cm-1/amagat (HWHM) at 293 K for J = 0-5, respectively.’ The pure rotational S0(J) lines (v = 0) of D2, self-broadened. Re-pointed to keijser_1974 (2026-09-27): its Table I (p. 595) prints nD2 0.084, 0.067, 0.062, 0.051, 0.043, 0.028 +- 0.001 GHz/amagat, HWHM (‘half the width at half intensity’, its p. 593) = 2.802, 2.235, 2.068, 1.701, 1.434, 0.934e-3 cm-1/amagat: these values to the printed digits (the original’s +-0.001 GHz = 0.033e-3 cm-1 is not quoted here). These are the room-temperature points of knaap_1979’s Fig. 6 (see that record), and exactly half of edwards_1991’s Table 8 ‘Knaap et al.’ values (5.6, 4.5, 4.1, 3.4, 2.9, printed there as 10^-3 cm-1 bar-1).
smyth_1987/o_branch_O4#
{
"id": "o_branch_O4",
"material": "D2",
"table": "text",
"quantity": "raman_linewidth",
"unit": "cm-1/amagat",
"scale": 0.001,
"abscissa": "label",
"use": "primary",
"parameters": {
"transition": "O1(4), v = 0 -> 1",
"width": "hwhm",
"perturber": "self"
}
}
1 inline points in the source record.
p. 1009: ‘In the case of the vibrational O1(4) line in pure D2 the measured line broadening coefficient is 2.50 x 10^-3 cm-1/amagat’, HWHM as the paper’s other coefficients (Eq. (1)), room temperature. No uncertainty stated. The paper compares it with (Q(2) + Q(4))/2 to infer an elastic reorientation contribution of 0.38e-3.
Formulas#
smyth_1987/eq1_dicke#
{
"id": "eq1_dicke",
"material": "D2",
"equation": "Eq. (1), p. 1004; D_0 values pp. 1005-1006",
"printed": "Gamma (HWHM, cm-1) = D_0 k^2 / 2 pi c rho + rho gamma",
"variable": "k = 2 pi nu_Raman (nu in cm-1, forward scattering); D_0 the (effective) diffusion coefficient at 1 amagat in cm2/s; c in cm/s; rho in amagat; gamma the HWHM line broadening coefficient in cm-1/amagat (Table I); the Dicke term D_0 k^2/(2 pi c rho) = 2 pi nu^2 D_0/(c rho)",
"state": "D2 at room temperature, pure and in mixtures",
"density": "unknown",
"range": "the Dicke regime k L << 1, above about 0.5 amagat in D2 (p. 1003); 0.28-20 amagat measured",
"coefficients": {
"D0_D2_Q1": "0.984",
"D0_D2_Q1_error": "0.022",
"D0_D2_Q2": "0.967",
"D0_D2_Q2_error": "0.022",
"D0_D2_mass": "0.950",
"D0_He_H2_mass": "1.16",
"D0_CH4": "0.471",
"D0_CH4_error": "0.02",
"D0_Ar": "0.438",
"D0_Ar_error": "0.02"
},
"check": "Against russell_1987's FWHM law (scratch, 2026-09-27): twice this Dicke term is (4 pi nu^2/c) D_0, Russell and Roh's Eq. (1) term, so the two laws agree in form. For Q(2) (nu = 2987 cm-1) D_0 = 0.967 gives 54.2 MHz amagat HWHM (108.4 FWHM), against Russell and Roh's 101.0 FWHM from D_0 = 0.901 (7 % apart, within Russell and Roh's D_0 error 0.06)."
}
D_0 of pure D2 at 298.5 K from Q(1) and Q(2) (two-line fits); no J dependence (p. 1005). 0.950 is the literature mass diffusion (Ref. 61). D2:He and D2:H2 used the literature mass diffusion 1.16 cm2/s at 296 K (Ref. 62) (p. 1005). D2:CH4 and D2:Ar from Q(1)-Q(2) at 298 K (p. 1006), 3.3 % and 17 % below the mass diffusion (0.487 and 0.530).
smyth_1987/table2_self#
{
"id": "table2_self",
"material": "D2",
"equation": "Eqs. (2)-(3), p. 1006; Table II (tbl_a413288f32f6), p. 1007",
"printed": "R_ji = alpha f(T0/T) [(1 + A E_i/kT delta)/(1 + A E_i/kT)]^2 exp(-beta Delta E_ij/kT) (E_i < E_j), R_ij from microscopic reversibility; gamma_j = 1/2 sum_{i != j} [R_ij(v = 0) + R_ij(v = 1)] + gamma_vib.dephasing",
"variable": "E_i the rotational term energy of the lower level J_i, Delta E_ij = E_j - E_i, kT, in cm-1; alpha and gamma_j (HWHM) in 10^-3 cm-1/amagat as printed; f(T0/T) = 1 (room temperature); R_ij(v = 0) = R_ij(v = 1), with the ground-state level spacings; A fixed per collision pair; case a: no dephasing; case b: the best J-independent dephasing term",
"state": "pure D2, room temperature",
"density": "unknown",
"range": "J = 0-5, room temperature (296.0-298.5 K)",
"coefficients": {
"A": "4.19",
"vd_a": "0",
"alpha_a": "12.6",
"delta_a": "0.943",
"beta_a": "1.70",
"rms_a": "0.13",
"vd_b": "0.51",
"vd_b_error": "0.19",
"alpha_b": "9.90",
"delta_b": "1.06",
"beta_b": "1.65",
"rms_b": "0.06"
},
"check": "Reproduces the printed rms deviation from Table I (scratch, 2026-09-27; rates summed to J = 20 over levels of the same parity, the downward rates by detailed balance, k = 0.6950348 cm-1/K, T = 297 K, D2 B = 29.8975 and D = 0.01117 cm-1 from data/gas/raman.toml, a stopgap fit to teal_1935): case a 0.129 (printed 0.13), case b 0.066 (printed 0.06); 0.066-0.070 over 296-298.5 K. Model case b: 2.96, 1.38, 1.97, 2.20, 2.09, 1.79 against 2.97, 1.33, 2.06, 2.13, 2.15, 1.71. This fixes the reading of Eq. (3): gamma_j is the total rate out of J (the two equal sums halved) plus the dephasing term."
}
Table II, ‘Pure D2’. vd: the vibrational dephasing contribution in 10^-3 cm-1/amagat; its error (note a) ‘is given by the change in the vibrational dephasing contribution that causes the rms deviation of the rate law fit to increase by +-20 %’. The rms deviation is of the fit to Table I, 10^-3 cm-1/amagat.
smyth_1987/table2_He#
{
"id": "table2_He",
"material": "D2",
"equation": "Eqs. (2)-(3), p. 1006; Table II (tbl_a413288f32f6), p. 1007",
"printed": "as table2_self",
"variable": "as table2_self; the perturber He",
"state": "D2 in He (5 %), room temperature",
"density": "unknown",
"range": "J = 0-5, room temperature",
"coefficients": {
"A": "3.40",
"vd_a": "0",
"alpha_a": "11.7",
"delta_a": "0.892",
"beta_a": "1.85",
"rms_a": "0.19",
"vd_b": "0.84",
"vd_b_error": "0.11",
"alpha_b": "8.15",
"delta_b": "1.16",
"beta_b": "1.97",
"rms_b": "0.04"
},
"check": "As table2_self (297 K): rms 0.186 (printed 0.19) and 0.036 (printed 0.04). Model case b: 2.34, 1.26, 1.67, 1.63, 1.43, 1.22 against 2.35, 1.20, 1.73, 1.62, 1.40, 1.21."
}
Table II, ‘D2:He’. The note added in proof: ab initio dephasing 0.80-0.99e-3 (J = 0, 2, 4) against this vd_b (p. 1010).
smyth_1987/table2_Ar#
{
"id": "table2_Ar",
"material": "D2",
"equation": "Eqs. (2)-(3), p. 1006; Table II (tbl_a413288f32f6), p. 1007",
"printed": "as table2_self",
"variable": "as table2_self; the perturber Ar",
"state": "D2 in Ar (10 % and 2.5 %), room temperature",
"density": "unknown",
"range": "J = 0-5, room temperature",
"coefficients": {
"A": "9.90",
"vd_a": "0",
"alpha_a": "15.4",
"delta_a": "0.813",
"beta_a": "1.76",
"rms_a": "0.51",
"vd_b": "2.25",
"vd_b_error": "0.40",
"alpha_b": "6.75",
"delta_b": "1.04",
"beta_b": "2.10",
"rms_b": "0.14"
},
"check": "As table2_self (297 K): rms 0.514 (printed 0.51) and 0.141 (printed 0.14). Model case b: 3.36, 2.56, 2.86, 2.84, 2.67, 2.51 against 3.37, 2.35, 3.11, 2.80, 2.58, 2.45; the paper: the fit with dephasing is within the experimental uncertainty 'for all systems except D2:Ar' (p. 1007)."
}
Table II, ‘D2:Ar’.
smyth_1987/table2_H2#
{
"id": "table2_H2",
"material": "D2",
"equation": "Eqs. (2)-(3), p. 1006; Table II (tbl_a413288f32f6), p. 1007",
"printed": "as table2_self",
"variable": "as table2_self; the perturber H2",
"state": "D2 in H2 (5 %), room temperature",
"density": "unknown",
"range": "J = 0-3 only (note b)",
"coefficients": {
"A": "2.79",
"vd_a": "0",
"alpha_a": "7.06",
"delta_a": "0.951",
"beta_a": "1.58",
"rms_a": "0.08",
"vd_b": "0.25",
"vd_b_error": "0.13",
"alpha_b": "6.21",
"delta_b": "1.01",
"beta_b": "1.61",
"rms_b": "0.05"
},
"check": "As table2_self (297 K), over J = 0-3: rms 0.079 (printed 0.08) and 0.048 (printed 0.05). Model case b: 1.85, 0.86, 1.22, 1.44 against 1.86, 0.81, 1.30, 1.42."
}
Table II, ‘D2:H2’, note b ‘J = 0-3 only’: Q(4), Q(5) are raised by near-resonant energy exchange with H2 (p. 1009).
smyth_1987/table2_CH4#
{
"id": "table2_CH4",
"material": "D2",
"equation": "Eqs. (2)-(3), p. 1006; Table II (tbl_a413288f32f6), p. 1007",
"printed": "as table2_self",
"variable": "as table2_self; the perturber CH4",
"state": "D2 in CH4 (10 %), room temperature",
"density": "unknown",
"range": "J = 0-5, room temperature",
"coefficients": {
"A": "9.44",
"vd_a": "0",
"alpha_a": "37.2",
"delta_a": "0.869",
"beta_a": "1.95",
"rms_a": "0.55",
"vd_b": "2.44",
"vd_b_error": "0.13",
"alpha_b": "34.6",
"delta_b": "0.949",
"beta_b": "2.37",
"rms_b": "0.04"
},
"check": "As table2_self (297 K): rms 0.552 (printed 0.55) and 0.048 (printed 0.04; 0.045-0.058 over 296-298.5 K). Model case b: 6.91, 3.67, 4.88, 4.75, 3.89, 3.21 against 6.94, 3.71, 4.90, 4.73, 3.97, 3.15."
}
Table II, ‘D2:CH4’.
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.