mikhailov_1959#
G. V. Mikhailov, “The influence of temperature and pressure on the Raman spectrum of nitrogen”, Sov. Phys. JETP 9, 974 (1959) [Zh. Eksp. Teor. Fiz. 36, 1368 (1959)]
Source record · Catalogue · Review register
No DOI is recorded.
Source kind: measurement
Recorded technique: Spontaneous Raman spectra of N2 gas at 27 C and 7-114 atm (and at 200 C, and of the liquid at -190 C), excited by the Hg 4047 and 4358 A lines in a high-pressure illuminator with a multiple-reflection mirror system, photographed with a HUET V-III spectrograph (22.7 cm-1/mm at 4047 A, 36.2 cm-1/mm at 4358 A) on Agfa plates, 3-40 h exposures; microphotometer traces, three or four plates per pressure. ‘the total width of the excitation line, of the slit, and of the apparatus function ... (~1.5 cm-1 for the gas ...) was excluded from the results’ (p. 2).
Materials in structured entries: N2
Dataset quantities: raman_linewidth
Contents: 8 datasets; 1 formula.
Curation notes#
IDENTITY. The library copy is the English translation, Sov. Phys. JETP 9, 974-978 (1959), whose first page reads ‘J. Exptl. Theoret. Phys. (U.S.S.R.) 36, 1368-1373 (May, 1959)’, ‘Submitted to JETP editor December 7, 1958’; the library identity is ASSERTED (no DOI). jammu_1966 and herring_1986 (Ref. 4, ‘G. V. Milahailov, Zh. Eksp. Teor. Fiz. 36, 1368 (1959) [Sov. Phys.-JETP 9, 974 (1959)]’) cite this paper. Page numbers are pdf pages 1-5.
solprop’s unverified ‘Sov. Phys. JETP 36, 9 (1959)’ for N2’s 6 ps is this paper: 36 is the Russian volume and 9 the translation’s volume of the same 1959 paper, the one the library’s papers (jammu_1966, herring_1986) cite as Mikhailov 1959. What it supports: 6 ps is 1/(pi Delta nu) for Delta nu = 1.77 cm-1 (solprop’s 53.05e9 Hz), and this paper’s width of the unresolved N2 Q branch at 27 C is 1.7-2.4 cm-1 at 15-114 atm (Table I) and 1.75 cm-1 calculated (1.8 +- 0.2 measured) at 50 atm (Table II), which give 6.1 ps and 5.9 ps. But that width is NOT a collisional dephasing width: ‘the rotational splitting introduces a basic length into the observed width of the Q branch’ (p. 4): delta nu_rot = 1.54 cm-1 of the 1.75 comes from the unresolved rotational structure (Q(J) spread by alpha J(J+1)), the collisional part being 0.2 cm-1 at 50 atm (Table II), about 0.005 cm-1/atm (formula collision_width with rho_nu = 0.43 A). The pressure-independent part extrapolated to zero pressure is 1.6 cm-1 (p. 4). So the 6 ps is the dephasing of the whole Q-branch envelope at room temperature, independent of pressure, and it is not a collision time.
WIDTH CONVENTION: not stated. The paper speaks only of ‘line width’ (delta omega, delta nu) measured on microphotometer traces after removing the apparatus width; whether it is the full width at half maximum or the half width is never said. Recorded as width = “not stated”. jammu_1966 (Table II) lists this author’s N2 coefficients as HWHM per atm, 47.5 and 26.5 x 10^-3 cm-1/atm below and above 25 atm, values that this paper’s Table I does not give directly (the slopes of Table I’s delta omega are about 0.16 cm-1/atm between 7 and 25 atm and 0.044 cm-1/atm between 25 and 80 atm): perhaps from the 1960 paper.
TABLE I (p. 2): ‘the average width for the transitions with J = 0 - 15 is given for the rotational lines’; ‘The average error in the measurements of the line widths comprised about 10 %’ (p. 2). The rotational lines overlap from 20 atm and blend above 80 atm; the slope changes at 25 atm (Fig. 3). The 3 atm width is ‘~0.5’ ‘Measured by V. A. Iozenas, Moscow State University’ (excluded: approximate, another observer). ‘The frequency shift of the Raman scattering lines lies within the limits of the errors of measurement (~1 cm-1)’ (p. 3).
TEXT (p. 3): at 200 C (the gas at ‘p = 90 atmos, reduced to 27 C’, i.e. the density of 90 atm at 27 C), delta omega = 8.5 +- 2 cm-1 and delta nu = 5.4 +- 1.5 cm-1 (inline datasets). Table II prints the 200 C row at ‘50 atmos’ at 27 C: the text and the table disagree on the density of the 200 C measurement (unresolved). Liquid N2 (-190 C): delta nu = 0.4 +- 0.2 cm-1, calculated 0.5 (0.45 + 0.05) at 0.5 g/cm3 (not extracted: not the gas).
CONSTANTS AND ERRORS. The Q-branch structure calculation (p. 4) uses ‘B = 1.998 cm-1, alpha = 0.171 cm-1 and T = 300 K’. alpha is printed ten times too large: bendtsen_1974 (Table VIII) gives alpha = 0.017292 cm-1 for 14N2, and the paper’s own delta nu_rot = 1.54 cm-1 needs the intensity scale kT alpha/B of about 1.8 cm-1, i.e. alpha about 0.017 (with 0.171 it would be 18 cm-1). Not recorded as data (an input of the calculation, uncited). The effective collision radius for the rotational lines is 3.9 A in the abstract but 3.3 A in the text (p. 3); neither reproduces Table I through the formula (see collision_width).
Recorded bibliographic identity status: ASSERTED. This concerns identification of the source; it does not establish the scientific correctness of its contents.
Datasets#
mikhailov_1959/table1_rotational#
{
"id": "table1_rotational",
"material": "N2",
"file": "N2/mikhailov_1959__table1_rotational.csv",
"table": "tbl_e9551d96728b",
"quantity": "raman_linewidth",
"unit": "cm-1",
"abscissa": "pressure",
"abscissa_unit": "atm",
"use": "primary",
"excluded_rows": {
"3atm": "printed '~0.5*': approximate, 'Measured by V. A. Iozenas, Moscow State University' (table note)"
},
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "rotational S and O lines, average over J = 0-15",
"width": "not stated",
"perturber": "self",
"temperature_k": 300.15
}
}
Table I (p. 2), delta omega: the width of the N2 pure rotational Raman lines, ‘the average width for the transitions with J = 0 - 15’, at 27 C, apparatus width removed; pure N2. Width convention not stated (see the source notes). Lines overlap from 20 atm; the slope changes at 25 atm.
mikhailov_1959/table1_vibrational#
{
"id": "table1_vibrational",
"material": "N2",
"file": "N2/mikhailov_1959__table1_vibrational.csv",
"table": "tbl_e9551d96728b",
"quantity": "raman_linewidth",
"unit": "cm-1",
"abscissa": "pressure",
"abscissa_unit": "atm",
"use": "primary",
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "Q branch, unresolved (v = 0 -> 1)",
"width": "not stated",
"perturber": "self",
"temperature_k": 300.15
}
}
Table I (p. 2), delta nu: the width of the unresolved N2 vibrational Q branch (v = 0 -> 1) at 27 C, apparatus width removed. Mostly the rotational structure of the branch (1.54 cm-1 calculated, 1.6 cm-1 extrapolated to zero pressure, p. 4), not a collisional width. Width convention not stated.
mikhailov_1959/text_rotational_200C#
{
"id": "text_rotational_200C",
"material": "N2",
"table": "text",
"quantity": "raman_linewidth",
"unit": "cm-1",
"abscissa": "none",
"use": "primary",
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "rotational S and O lines, average over J",
"width": "not stated",
"perturber": "self",
"temperature_k": 473.15
}
}
1 inline points in the source record.
p. 3: ‘the nitrogen lines are wider at 200 C than at room temperature: delta omega = 8.5 +- 2 cm-1’, at ‘p = 90 atmos, reduced to 27 C’ (the density of 90 atm at 27 C; Table II says 50 atm for its 200 C row). Rotational lines, J-averaged as in Table I. Width convention not stated.
mikhailov_1959/text_vibrational_200C#
{
"id": "text_vibrational_200C",
"material": "N2",
"table": "text",
"quantity": "raman_linewidth",
"unit": "cm-1",
"abscissa": "none",
"use": "primary",
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "Q branch, unresolved (v = 0 -> 1)",
"width": "not stated",
"perturber": "self",
"temperature_k": 473.15
}
}
1 inline points in the source record.
p. 3: ‘delta nu = 5.4 +- 1.5 cm-1’ for the unresolved Q branch at 200 C, ‘p = 90 atmos, reduced to 27 C’; repeated in Table II (experimental, 200 C, where the density is given as 50 atm at 27 C). Width convention not stated.
mikhailov_1959/table2_rotational_structure#
{
"id": "table2_rotational_structure",
"material": "N2",
"file": "N2/mikhailov_1959__table2_rotational_structure.csv",
"table": "tbl_57a9c368f39b",
"quantity": "raman_linewidth",
"unit": "cm-1",
"abscissa": "label",
"columns": {
"temperature": "C"
},
"use": "check",
"parameters": {
"transition": "Q branch, unresolved (v = 0 -> 1)",
"width": "not stated"
}
}
Table II (p. 4), ‘Calculated for the gas’, delta nu_rot: the width of the unresolved rotational structure of the N2 Q branch (the averaged intensity distribution of p. 4 with B = 1.998 cm-1 and alpha printed 0.171 cm-1; see the source notes), at the density of 50 atm at 27 C. Not a collisional width.
mikhailov_1959/table2_collisional#
{
"id": "table2_collisional",
"material": "N2",
"file": "N2/mikhailov_1959__table2_collisional.csv",
"table": "tbl_57a9c368f39b",
"quantity": "raman_linewidth",
"unit": "cm-1",
"abscissa": "label",
"columns": {
"temperature": "C"
},
"use": "check",
"parameters": {
"transition": "Q branch (v = 0 -> 1)",
"width": "not stated",
"perturber": "self"
}
}
Table II (p. 4), ‘Calculated for the gas’, delta nu_col: the collisional width of the Q branch from delta = 2 pi N v rho^2 with rho_nu = 0.43 A, at the density of 50 atm at 27 C (formula collision_width: 0.027 x 0.43^2 x 50 = 0.25 cm-1 at 27 C, printed 0.2).
mikhailov_1959/table2_total#
{
"id": "table2_total",
"material": "N2",
"file": "N2/mikhailov_1959__table2_total.csv",
"table": "tbl_57a9c368f39b",
"quantity": "raman_linewidth",
"unit": "cm-1",
"abscissa": "label",
"columns": {
"temperature": "C"
},
"use": "check",
"parameters": {
"transition": "Q branch, unresolved (v = 0 -> 1)",
"width": "not stated",
"perturber": "self"
}
}
Table II (p. 4), ‘Calculated for the gas’, delta nu = delta nu_rot + delta nu_col, at the density of 50 atm at 27 C. The 27 C value, 1.75 cm-1, is 1/(pi c x 6.06 ps): the width solprop’s 6 ps N2 dephasing time corresponds to.
mikhailov_1959/table2_experimental#
{
"id": "table2_experimental",
"material": "N2",
"file": "N2/mikhailov_1959__table2_experimental.csv",
"table": "tbl_57a9c368f39b",
"quantity": "raman_linewidth",
"unit": "cm-1",
"abscissa": "label",
"columns": {
"temperature": "C"
},
"use": "check",
"uncertainty": {
"column": true,
"level": "not stated"
},
"parameters": {
"transition": "Q branch, unresolved (v = 0 -> 1)",
"width": "not stated",
"perturber": "self"
}
}
Table II (p. 4), ‘Experimental’ delta nu of the Q branch: the 200 C value repeats the text’s 5.4 +- 1.5 (text_vibrational_200C, whose density the text gives as 90 atm at 27 C, the table as 50 atm); the 27 C value, 1.8 +- 0.2, lies between Table I’s 40 and 60 atm values.
Formulas#
mikhailov_1959/collision_width#
{
"id": "collision_width",
"material": "N2",
"equation": "text, p. 3",
"printed": "delta = 0.027 rho^2 p (from delta = 2 pi N v rho^2)",
"variable": "rho: the effective optical collision radius in A; p: pressure in atm; delta: the line width in cm-1; N2 at 27 C",
"state": "pure N2 at 27 C",
"density": "ideal",
"range": "0-25 atm (the collision-broadening region for the rotational lines, p. 3)",
"coefficients": {
"k": "0.027",
"rho_rotational_text": "3.3",
"rho_rotational_abstract": "3.9",
"rho_vibrational": "0.43"
},
"check": "Scratch, 2026-09-26: with rho_nu = 0.43 A, 0.0050 cm-1/atm, 0.25 cm-1 at 50 atm (Table II delta nu_col 0.2 at 27 C). With rho_omega = 3.3 A (text) 0.294 cm-1/atm and with 3.9 A (abstract) 0.41 cm-1/atm, whereas Table I's rotational widths rise by 0.164 cm-1/atm between 7 and 25 atm (4.7 cm-1 at 25 atm against 7.4 from the formula with 3.3 A): the rotational radius does not reproduce Table I. The 0.027 prefactor equals 2 pi N v rho^2 / c at 1 atm and 300.15 K (N = 2.445e19 cm-3) with v = 527 m/s, about the rms speed of N2 (517 m/s)."
}
Collision (impact) theory, p. 3, citing Sobel’man (Ref. 7); the width convention is not stated.
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.