peck_1966#
E. R. Peck and B. N. Khanna, J. Opt. Soc. Am. 56, 1059 (1966)
Source record · Catalogue · Review register
No DOI is recorded.
Source kind: measurement
Recorded technique: Corner-reflector interferometer with a 24 cm gas cell in one arm and two light sources at once (a visible reference line and a second line), fringes counted as the gas is admitted and pumped out and interpolated to 0.001 order; refractivity ratios independent of cell length and density. Pressure by wide-bore mercury manometer (local g = 980.302 cm/s^2), temperature by thermocouple. Matheson N2, 99.996 %, through a dry-ice cold trap.
Materials in structured entries: N2
Dataset quantities: refractivity, verdet_constant_ratio
Contents: 5 datasets; 9 formulas.
Curation notes#
Identity: the library record is UNVERIFIED; the text is ‘Dispersion of Nitrogen’ by Edson R. Peck and Baij Nath Khanna (Northwestern University, received 3 December 1965), file josa-56-8-1059.pdf, which matches the citation J. Opt. Soc. Am. 56, 1059-1063 (1966) given for it by Griesmann (1999) and Peck & Huang (1977). No DOI is recorded (the library has none).
Reduction: to one atmosphere at T0 with the factor K of Eq. (2), the real-gas compressibility Z = 1 - p (317.60 - T) 1e-5 (Eq. 1, p in atm, from Hilsenrath’s tables, ‘developed under the old convention of 0 C = 273.16 K’) and a small Lorentz-Lorenz correction: density = real. Wavelengths are vacuum (Table I heading).
Table I gives relative values: ‘a nominal value of 10^8 (n - 1) = 28 352.40 at 15 C is taken for the mercury green line at vacuum wavelength 5462.258 A; other values of refractivity are expressed in terms of this as a standard’ (p. 1060). The absolute measurement at 5462.258 A is 28 352.4 +- 1.6 at 15 C and 1 atm (statistical standard deviation of 22 sets of runs), ‘significant only to about four digits’; with ‘a realistic estimate of total error’, 10^6 (n - 1) = 299.14 +- 0.10 at 0 C (p. 1060). The relative values are about two orders of magnitude more precise: the rms deviation of the 16 fitted points from Eq. (3) is 0.083e-8, ‘considered to be a better representation of precision than the individual standard deviations’ (p. 1061). Hence per point absolute = 0.083 (rms) and systematic_relative = 3.3e-4 (0.10 / 299.14, the realistic total error, level not stated, taken as one sigma). The 0 C absolute value is the same measurement converted, so it is not a separate dataset.
Three points (5087.242, 7034.352, 13507.884 A) are printed in parentheses and were omitted from the fit as ‘excessively far from the trend’ (the 7034 A neon line has an unresolved weak neighbour, p. 1061). Table II gives the dispersion of the Verdet constant as ratios to its value at 5780 A (air wavelengths), computed from Eq. (3) and measured by Ingersoll & Liebenberg (1954); the computed column is a check of the formula, the measured one a reproduction. Other results: n_inf - 1 = 293.77e-6 at 0 C from Eq. (4) (p. 1062; all formulas agree within 0.01e-6); Verdet factor r = 0.636 at 5462 A; the Rayleigh cross section 0.5182e-28 cm^2 at 30 degrees, 6945.165 A in vacuo (p. 1063). Svensson’s air formula (p. 1061) is skipped (air is not a species).
Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.
Datasets#
peck_1966/experiment#
{
"id": "experiment",
"material": "N2",
"file": "N2/peck_1966__experiment.csv",
"table": "tbl_c2970086b7ad",
"quantity": "refractivity",
"scale": 1e-08,
"abscissa_unit": "angstrom",
"wavelength_medium": "vacuum",
"state": "1atm_15C",
"density": "real",
"use": "primary",
"uncertainty": {
"absolute": 0.083,
"level": "rms",
"systematic_relative": 0.00033
}
}
The 16 fitted points, standardised to 28352.40 at 5462.258 A (the absolute scale, +-3.3e-4, is the systematic uncertainty).
peck_1966/experiment_excluded#
{
"id": "experiment_excluded",
"material": "N2",
"file": "N2/peck_1966__experiment_excluded.csv",
"table": "tbl_c2970086b7ad",
"quantity": "refractivity",
"scale": 1e-08,
"abscissa_unit": "angstrom",
"wavelength_medium": "vacuum",
"state": "1atm_15C",
"density": "real",
"use": "excluded"
}
The three values printed in parentheses, 0.42, 1.44 and 0.65 (x 1e-8) from Eq. (3), omitted from the fit; ‘the more correct value is given by the formula’ (p. 1061).
peck_1966/eq3#
{
"id": "eq3",
"material": "N2",
"file": "N2/peck_1966__eq3.csv",
"table": "tbl_c2970086b7ad",
"quantity": "refractivity",
"scale": 1e-08,
"abscissa_unit": "angstrom",
"wavelength_medium": "vacuum",
"state": "1atm_15C",
"density": "real",
"use": "check"
}
Table I ‘Calculated refractivity’: Eq. (3) at the measured wavelengths.
peck_1966/verdet_ratio_eq3#
{
"id": "verdet_ratio_eq3",
"material": "N2",
"file": "N2/peck_1966__verdet_ratio_eq3.csv",
"table": "tbl_029c38d597ef",
"quantity": "verdet_constant_ratio",
"unit": "1",
"abscissa_unit": "angstrom",
"wavelength_medium": "standard_air",
"state": "1atm_15C",
"density": "real",
"use": "check",
"parameters": {
"reference_wavelength_nm": 578.0
}
}
Table II ‘Computed ratio’: V(lambda)/V(5780 A) from Eq. (3) through V/r proportional to sigma dn/dsigma (p. 1062), with r constant. The ratio is independent of the state to first order; the state is Eq. (3)’s. Row ‘5460-61’ placed at 5460.5 A.
peck_1966/verdet_ratio_ingersoll_liebenberg#
{
"id": "verdet_ratio_ingersoll_liebenberg",
"material": "N2",
"file": "N2/peck_1966__verdet_ratio_ingersoll_liebenberg.csv",
"table": "tbl_029c38d597ef",
"quantity": "verdet_constant_ratio",
"unit": "1",
"abscissa_unit": "angstrom",
"wavelength_medium": "standard_air",
"state": "1atm_15C",
"density": "unknown",
"use": "reproduced",
"reproduced_from": [
"L. Ingersoll and D. Liebenberg, J. Opt. Soc. Am. 44, 566 (1954)"
],
"parameters": {
"reference_wavelength_nm": 578.0
}
}
Table II ‘Ratio measured by Ingersoll and Liebenberg’: V(lambda)/V(5780 A). The ratio to the dispersion formula (the factor r of the Becquerel-Serber relation) is constant within 4.4 % over 3635-9875 A (p. 1063); r itself is 0.636 at 5462 A, so these ratios constrain dn/dsigma only through an assumed constant r. The state is nominal (the ratio does not depend on it to first order).
Formulas#
peck_1966/eq3#
{
"id": "eq3",
"form": "dn_sigma2",
"terms": {
"scale": "1e-8",
"A": "6497.378",
"B": [
"3073864.9"
],
"C": [
"144"
]
},
"range_nm": [
467.9,
2058.7
],
"material": "N2",
"equation": "Eq. (3), p. 1061",
"printed": "10^8 (n - 1) = 6497.378 + 3073864.9/(144 - sigma^2) (15 C)",
"variable": "sigma: vacuum wavenumber in um^-1",
"state": "1atm_15C",
"density": "real",
"range": "4679-20587 A (the data)",
"coefficients": {
"A": "6497.378",
"B": "3073864.9",
"C": "144"
},
"check": "Reproduces Table I's calculated column to 0.01 at all 19 wavelengths; rms 0.083 over the 16 fitted points as stated (checked 2026-09-24)."
}
The paper’s representation of its data. ‘A slightly better statistical fit is obtained by using a constant of 143.647215’ (p. 1061), not given in full.
peck_1966/eq4#
{
"id": "eq4",
"form": "dn_sigma2",
"terms": {
"scale": "1e-8",
"A": "6855.200",
"B": [
"3243157.0"
],
"C": [
"144"
]
},
"range_nm": [
467.9,
2058.7
],
"material": "N2",
"equation": "Eq. (4), p. 1061",
"printed": "10^8 (n - 1) = 6855.200 + 3243157.0/(144 - sigma^2) (0 C)",
"variable": "sigma: vacuum wavenumber in um^-1",
"state": "1atm_0C",
"density": "real",
"range": "4679-20587 A",
"coefficients": {
"A": "6855.200",
"B": "3243157.0",
"C": "144"
},
"check": "Eq. (3) times 1.05507 in both coefficients, the real-gas density ratio 288.16/273.16 x Z(15 C)/Z(0 C) = 1.055071 from Eq. (1); n_inf - 1 = 293.77e-6 as stated (checked 2026-09-24)."
}
Eq. (3) referred to 0 C: not independent.
peck_1966/eq5#
{
"id": "eq5",
"material": "N2",
"equation": "Eq. (5), p. 1061",
"printed": "10^8 (n - 1) = 5109702.9/(183.69459 - sigma^2) + 212.949/(7.74396 + sigma^2) (15 C)",
"variable": "sigma: vacuum wavenumber in um^-1",
"state": "1atm_15C",
"density": "real",
"range": "4679-20587 A",
"coefficients": {
"B1": "5109702.9",
"C1": "183.69459",
"B2": "212.949",
"C2": "-7.74396"
},
"check": "rms 0.075 over the 16 fitted points as stated (checked 2026-09-24)."
}
The second term has ‘+ sigma^2’ in its denominator as printed (a pole at imaginary wavenumber); coefficient C2 is given with the sign that makes it a standard B/(C - sigma^2) term.
peck_1966/eq6#
{
"id": "eq6",
"material": "N2",
"equation": "Eq. (6), p. 1061",
"printed": "10^8 (n - 1) = 5189259.2/(186.3764 - sigma^2) (15 C)",
"variable": "sigma: vacuum wavenumber in um^-1",
"state": "1atm_15C",
"density": "real",
"range": "4679-20587 A",
"coefficients": {
"B": "5189259.2",
"C": "186.3764"
},
"check": "rms 0.364 over the 16 points (paper: 0.363) (checked 2026-09-24)."
}
Single-term fit, systematic trend; used for the effective oscillator (732.5 A, f = 4.54).
peck_1966/eq7#
{
"id": "eq7",
"material": "N2",
"equation": "Eq. (7), p. 1061",
"printed": "10^8 (n - 1) = 5475062.8/(186.3764 - sigma^2) (0 C)",
"variable": "sigma: vacuum wavenumber in um^-1",
"state": "1atm_0C",
"density": "real",
"range": "4679-20587 A",
"coefficients": {
"B": "5475062.8",
"C": "186.3764"
},
"check": "Eq. (6) times 1.05508 (checked 2026-09-24)."
}
Eq. (6) referred to 0 C.
peck_1966/cuthbertson_1910#
{
"id": "cuthbertson_1910",
"material": "N2",
"equation": "p. 1062 (text)",
"printed": "10^8 (n - 1) = 5.5939 x 10^6/(189.944 - sigma^2) (Cuthbertson and Cuthbertson)",
"variable": "sigma: vacuum wavenumber in um^-1 (converted by Peck & Khanna assuming c = 3e10 cm/s in the original)",
"state": "1atm_0C",
"range": "not stated",
"coefficients": {
"B": "5.5939e6",
"C": "189.944"
},
"reproduced_from": [
"C. Cuthbertson and M. Cuthbertson, Proc. Roy. Soc. (London) 83A, 151 (1910)"
],
"check": "Not checked."
}
Converted by Peck & Khanna from the original frequency form; state as for their comparison with Eq. (7) (0 C), not stated explicitly.
peck_1966/tausz_1931#
{
"id": "tausz_1931",
"material": "N2",
"equation": "p. 1062 (text)",
"printed": "10^8 (n - 1) = 5.3607 x 10^6/(182.585 - sigma^2) (Tausz and Gorlacher)",
"variable": "sigma: vacuum wavenumber in um^-1 (converted with the modern c)",
"state": "1atm_0C",
"range": "not stated",
"coefficients": {
"B": "5.3607e6",
"C": "182.585"
},
"reproduced_from": [
"J. Tausz and H. Gorlacher, Z. Tekhn. Phys. 12, 19, 123 (1931)"
],
"check": "Not checked."
}
Converted by Peck & Khanna; state not stated explicitly (compared with Eq. 7).
peck_1966/koch_1913#
{
"id": "koch_1913",
"material": "N2",
"equation": "p. 1062 (text)",
"printed": "(3/2) 10^8 (n^2 - 1)/(n^2 + 2) = 3953450/(152.294 - sigma^2) + 837340/(240.651 + sigma^2) (Koch)",
"variable": "sigma: wavenumber in um^-1",
"range": "not stated",
"coefficients": {
"B1": "3953450",
"C1": "152.294",
"B2": "837340",
"C2": "-240.651"
},
"reproduced_from": [
"J. Koch, Arkiv Math. Astron. Fysik 9 (No. 6), 1 (1913)"
],
"check": "Not checked."
}
Fits the Lorentz-Lorenz function, not n - 1; ‘+ sigma^2’ in the second denominator as printed.
peck_1966/wilkinson_1960#
{
"id": "wilkinson_1960",
"material": "N2",
"equation": "p. 1062 (text)",
"printed": "10^8 (n - 1) = 6.3622 x 10^4/(45.989 - sigma^2) + 32453 x 10^6/(1065.11 - sigma^2) (Wilkinson)",
"variable": "sigma: vacuum wavenumber in um^-1 (converted by Peck & Khanna)",
"range": "Wilkinson's far-ultraviolet data",
"coefficients": {
"B1": "6.3622e4",
"C1": "45.989",
"B2": "32453e6",
"C2": "1065.11"
},
"reproduced_from": [
"P. G. Wilkinson, J. Opt. Soc. Am. 50, 1002 (1960)"
],
"check": "Not checked. Griesmann & Burnett (1999) find it valid only between 180 and 200 nm."
}
Peck & Khanna also give a refit of Wilkinson’s data, 10^8 (n - 1) = 3.76527e5/(58.0332 - sigma^2) + 2.48645e6/(83.7400 + sigma^2), which lowers the rms and mean absolute deviations to 87 % and 92 % (p. 1062).
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.