bruce_1990#

M. R. Bruce, W. B. Layne, C. A. Whitehead and J. W. Keto, “Radiative lifetimes and collisional deactivation of two-photon excited xenon in argon and xenon”, J. Chem. Phys. 92, 2917-2926 (1990)

Source record · Catalogue · Review register

DOI: 10.1063/1.457939

Source kind: measurement

Recorded technique: Two-photon excitation of Xe 5p5 6p, 6p’ and 7p (J = 0, 2) by a linearly polarised, frequency-doubled dye laser pumped by a 1 kHz XeCl laser; time-correlated single-photon counting of the near-infrared and visible fluorescence (Table I’s lines; JY 640 monochromator, cooled RCA 8852 photomultiplier; instrument response 660 ps FWHM, fully deconvolved by nonlinear least squares) and of the collisionally induced VUV fluorescence of 5d[1/2]1 at 125.0 nm (1 m Seya monochromator, 10 Angstrom resolution). Stern-Volmer plots of the decay rate nu = nu_rad + k_Xe [Xe] + k_Ar [Ar] (plus a three-body term for 6p[1/2]0 in xenon) in pure xenon (1e-4 to 1000 Torr) and in argon (up to 400 Torr, xenon fixed at 0.004-1 Torr); radiative lifetimes from the zero-pressure intercepts in pure xenon. Room temperature (the detailed balance at ‘300 K’). Errors are two standard deviations throughout.

Materials in structured entries: Xe

Dataset quantities: collisional_quenching_rate_coefficient, radiative_lifetime

Contents: 13 datasets; 0 formulas.

Curation notes#

J. Chem. Phys. 92(5), 2917-2926 (1 March 1990) = PDF pages 2-11 (PDF page 1 is the AIP download cover; journal page = PDF page + 2915). Identity checked on the first page of the article (PDF p. 2: title, authors, University of Texas at Austin, received 28 July 1989, accepted 21 August 1989, footer J. Chem. Phys. 92 (5), 1 March 1990, 2917) on 2026-10-09. Tables I-IV checked cell by cell against the table images; the appendix rate scheme on the rendered pages (pp. 2925-2926).

TAKEN (radiative_lifetime and collisional_quenching_rate_coefficient, TC-1011; extraction script tools/extract/bruce_1990.py for the tables, inline points for the appendix): the column ‘This work’ of Tables II, III and IV and the appendix’s state-to-state rates, all ‘two standard deviations’ (p. 2919, appendix). Rows are the levels in the paper’s notation; their NIST levels below. Room temperature, not stated as a number (the detailed balance uses ‘300 K’); no temperature_k is given.

LEVELS. The paper uses modified Racah notation, the last number J (Fig. 1). NIST (src/optmat/data/external/nist_asd/Xe_I_levels.tsv): 6p[5/2]2 = 5p5(2P*3/2)6p 2[5/2], J = 2 (78119.798 cm-1); 6p[3/2]2 = (2P*3/2)6p 2[3/2], J = 2 (79212.465); 6p[1/2]0 = (2P*3/2)6p 2[1/2], J = 0 (80118.962); 7p[5/2]2, 7p[3/2]2, 7p[1/2]0 = (2P*3/2)7p, 88351.681, 88686.500, 88842.256; 6p’[3/2]2 and 6p’[1/2]0 = (2P*1/2)6p 2[3/2] J = 2, 89162.356, and 2[1/2] J = 0, 89860.015; 5d[1/2]1 = (2P*3/2)5d 2[1/2]*, J = 1 (79986.618). Evidence: Table I’s vacuum wavelengths of the monitored lines, 904.8, 823.4, 828.2, 492.5, 462.6, 480.8, 834.9, 789.0 and 125.0 nm, equal NIST’s 904.79, 823.39, 828.24, 492.45, 462.56, 480.84, 834.91, 788.96 and 125.02 nm for those transitions; and the 5d[1/2]1 - 6p[1/2]0 gap ‘132.3 cm-1’ and 5d[7/2]4 ‘77.7 cm-1 above’ (p. 2921) equal NIST’s 132.344 and 77.667 cm-1.

WHAT IS TAKEN, AND HOW: - Table III (p. 2922), radiative lifetimes (ns): 6p[5/2]2 36.0 +- 2.8; 6p[3/2]2 31.3 +- 1.8; 6p[1/2]0 26.8 +- 0.8; 7p[5/2]2 128.6 +- 5.6; 7p[3/2]2 105.3 +- 2.9; 7p[1/2]0 69.1 +- 1.3; 6p’[3/2]2 32.1 +- 0.8; 6p’[1/2]0 34.1 +- 0.8 (tau_Xe, primary); 5d[1/2]1 111 +- 16 (tau_5d_Xe, check: ‘Although the state is radiation trapped, this measurement of the radiative lifetime should be good to within the quoted errors’, p. 2922; from Fig. 11’s intercept of rates that are themselves intercepts; NIST 65.6 ns). Not taken: text p. 2919, 6p[5/2]2 from the data below 20 Torr, 36 +- 4 ns and (110 +- 7) x 10^-12 cm3/s, a subset of the same measurement. - Table II (p. 2919), total quenching by xenon (perturber self): bimolecular (10^-12 cm3/s), nine levels, 6p[5/2]2 116 +- 3; 6p[3/2]2 101 +- 3; 6p[1/2]0 5.9 +- 0.5; 5d[1/2]1 197 +- 26 (footnote c: from the zero-argon-pressure intercepts, Fig. 11); 7p[5/2]2 462 +- 9; 7p[3/2]2 522 +- 8; 7p[1/2]0 493 +- 8; 6p’[3/2]2 426 +- 10; 6p’[1/2]0 423 +- 8 (kq_self_Xe, primary); termolecular (10^-31 cm6/s), 6p[1/2]0 7.0 +- 0.5 (kq3_self_Xe, primary); 6p[3/2]2 ‘<4’, ‘Our present error bars put a limit on a three body quenching term of <4 x 10^-31 cm6/s’ (p. 2925), held as the interval 0 to 4, value 2 with a bound half-width 2 (kq3_bound_Xe, check). - Table IV (p. 2923), total quenching by argon (10^-12 cm3/s): the seven levels with a single-exponential decay, 6p[3/2]2 40 +- 2.0; 6p[5/2]2 82 +- 4.0; 7p[1/2]0 256 +- 34; 7p[3/2]2 348 +- 32; 7p[5/2]2 259 +- 20; 6p’[1/2]0 247 +- 14; 6p’[3/2]2 179 +- 14 (kq_Ar_Xe, primary). The coupled pair (kq_Ar_coupled_Xe, check): 6p[1/2]0 200 +- 4.0 (footnote b, the fast component), 5d[1/2]1 5.9 +- 0.4 (c, the slow component) and 5.5 +- 0.4 (d, from the 125 nm fluorescence). These are the argon slopes of the two decay eigenvalues of the coupled 6p[1/2]0 / 5d[1/2]1 pair, not the levels’ removal coefficients: with the appendix’s rates, lambda+ / [Ar] = k12 (1 + chi) = 199.8 (Eq. A11) and lambda- / [Ar] = (k10 chi + k20) / (1 + chi) = 5.85 (Eq. A12), reproducing 200 and 5.9 (script check). The removal coefficients are the appendix’s k1 = 183 +- 6 (6p[1/2]0) and k2 = 34 +- 2 (5d[1/2]1). - Appendix (pp. 2925-2926), perturber Ar, 10^-12 cm3/s, inline points (primary): 6p[1/2]0 -> 5d[1/2]1, k12 = 170 +- 3 (k12_Ar); 6p[1/2]0 -> other Xe* states, k10 = 13 +- 6 (k10_Ar); 6p[1/2]0 total, k1 = 183 +- 6 (k1_Ar); 5d[1/2]1 -> 6p[1/2]0, k21 = 30 +- 1 (k21_Ar); 5d[1/2]1 -> other Xe* states, k20 = 4.6 +- 1.6 (k20_Ar; the straightforward Eq. (A10) analysis gives 4.2 +- 4.6, the printed value uses Eq. (A12) with k10); 5d[1/2]1 total, k2 = 34 +- 2 (k2_Ar). Script checks: k21 = chi k12 = 29.8, k1 = k12 + k10 = 183, k2 = k21 + k20 = 34.6. Not taken: 5d[1/2]1 + Xe, k_Xe5d = 197 +- 27, Table II’s 197 +- 26 (taken there) with a different error. - Not taken: the other references’ columns of Tables II-IV (reproduced) and the Stern-Volmer figures (Figs. 4-11), whose slopes and intercepts are the tables’ values; the detailed balance chi = 0.1752 (Eq. A9, derived from the level energies).

FINDING (NIST lifetimes, 1/sum A over the NIST lines from the level, Xe_I_lines.tsv and Xe_I_lines_nir.tsv, TC-983; tp_ref in brackets). 6p[5/2]2: lines to 6s[3/2]2 and 6s[3/2]1, 1/sum A = 39.4 ns against 36.0 +- 2.8 (NIST 1.09 times longer). 6p[3/2]2: to 6s[3/2]2 and 6s[3/2]1 (the 4932 nm line to 6s’[1/2]1 has no A), 27.3 ns against 31.3 +- 1.8 (0.87). 6p[1/2]0: to 6s[3/2]1 only (3408 nm to 6s’[1/2]1, no A), 27.1 ns against 26.8 +- 0.8 (1.01). 7p[5/2]2: 11 lines to 6s, 6s’, 5d and 7s, 129.2 ns against 128.6 +- 5.6; 7p[3/2]2: 11 lines, 106.4 ns against 105.3 +- 2.9; 7p[1/2]0: 5 lines, 69.0 ns against 69.1 +- 1.3 (all three within 1 %; NIST T8608n, T6672, the ‘n’ presumably a normalisation, perhaps to these lifetimes; not resolved here). 6p’[3/2]2: lines to 6s[3/2]2, 6s[3/2]1 and 6s’[1/2]1 (six lines to 5d and 7s without A), 22.8 ns against 32.1 +- 0.8 (0.71). 6p’[1/2]0: to 6s[3/2]1 and 6s’[1/2]1 (three lines to 5d and 7s without A), 27.6 ns against 34.1 +- 0.8 (0.81). For the 6p’ levels the NIST main line alone, 834.91 nm A = 4.2e7 (C+) and 788.96 nm A = 3.5e7 (C+), exceeds the measured total decay rate (3.12e7 and 2.93e7 s-1): the missing branches can only shorten NIST’s lifetimes further. 5d[1/2]1: 125.02 nm and 3680 nm, 65.6 ns against 111 +- 16 (radiation trapped, the paper says). The other measurements of Table III scatter as widely (6p[3/2]2: 28-48 ns).

FINDING (sabbagh_1977). 6p[1/2]0 decays only by 828.2 nm, so 26.8 ns gives A = 3.73e7 s-1 against Sabbagh and Sadeghi’s adopted reference 34 +- 2.5 x 10^6 s-1 and NIST’s 3.69e7.

DOUBTS (printed inconsistencies; no taken value is corrected): the 5d[1/2]1 xenon rate is 197 +- 26 (Table II), ‘(196 +- 26) x 10^-12’ (text p. 2922) and 197 +- 27 (appendix). Moutard et al.’s (Ref. 26) termolecular rate of 6p[3/2]2 is ‘6.5 +- 5’ in Table II’s 10^-31 cm6/s but ‘6.5 +- 0.5 x 10^-30 cm6/s’ in the note added in proof (p. 2925), a factor 10 apart. Table IV’s 6p[1/2]0 argon rate, 200 +- 4.0, differs from the appendix’s total k1 = 183 +- 6, and its 5d[1/2]1 rates, 5.9 and 5.5, from k2 = 34 +- 2: explained above (eigenvalue slopes, not removal coefficients), though Table IV calls them all ‘Total bimolecular reaction rates’. chi = (1/3) exp(-132.3 cm-1 / kT) is 0.1767 at 300 K; the printed 0.1752 corresponds to 296 K. The text writes ‘5d[1/2]0’ for 5d[1/2]1 (p. 2920 and Table IV’s footnote d) and the appendix’s last sentence ‘6p[1/2]1’ for 6p[1/2]0.

BEARING ON OEP 8 (for scale, not data): quenching depopulates the level and is not the pure dephasing gamma_phi. 6p[1/2]0 in xenon, 5.9 x 10^-12 cm3/s, is 1.9e5 s-1 per Torr at 296 K (3.26e16 cm-3), a Lorentzian FWHM of 0.03 MHz/Torr, about 800 times below the pressure broadening of 25 +- 15 MHz/Torr that gornik_1981 quotes from Hawkins et al. (1980; not in the library): the line’s pressure width is elastic dephasing, not quenching. 6p[3/2]2 and 6p[5/2]2 are quenched 17-20 times faster (0.52 and 0.60 MHz/Torr).

TWO-PHOTON DATA CITED, NOT IN THE LIBRARY: N. Bowering, M. R. Bruce and J. W. Keto, J. Chem. Phys. 84, 709 and 715 (1986) (two-photon excitation of Xe 6p, lifetimes and quenching); J. K. Ku and D. W. Setser, J. Chem. Phys. 84, 4304 (1986) (two-photon excitation of Xe 6p in Ar and Xe); P. Moutard, P. Laporte, J. L. Subtil and H. Damany, Chem. Phys. Lett. 132, 521 (1986) (two-photon quenching of Xe 6p[1/2]0 and 6p[3/2]2); N. Bowering, T. D. Raymond and J. W. Keto, Phys. Rev. Lett. 52, 1880 (1984) (optical collisions near 6p[1/2]0); T. D. Raymond, N. Bowering, C.-Y. Kuo and J. W. Keto, Phys. Rev. A 29, 721 (1984) (two-photon spectroscopy of Xe2/Xe* 6p).

Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.

Datasets#

bruce_1990/tau_Xe#

{
  "id": "tau_Xe",
  "material": "Xe",
  "file": "Xe/bruce_1990__tau_Xe.csv",
  "table": "tbl_3cb99347e778",
  "quantity": "radiative_lifetime",
  "unit": "ns",
  "abscissa": "label",
  "use": "primary",
  "parameters": {
    "method": "two-photon laser excitation, time-correlated photon counting with the 660 ps instrument response deconvolved, zero-pressure intercept of the Stern-Volmer plot in pure xenon (from 1e-4 Torr)"
  },
  "uncertainty": {
    "column": true,
    "level": "2 sigma"
  }
}

Table III (p. 2922), row ‘This work’: the radiative lifetimes of the two-photon excited 6p[5/2]2, 6p[3/2]2, 6p[1/2]0, 7p[5/2]2, 7p[3/2]2, 7p[1/2]0, 6p’[3/2]2 and 6p’[1/2]0, 26.8-128.6 ns, 2 sigma. NIST 1/sum A (record notes): within 1 % for 6p[1/2]0 and the 7p levels; 39.4 and 27.3 ns for 6p[5/2]2 and 6p[3/2]2; 22.8 and 27.6 ns for 6p’[3/2]2 and 6p’[1/2]0.

bruce_1990/tau_5d_Xe#

{
  "id": "tau_5d_Xe",
  "material": "Xe",
  "file": "Xe/bruce_1990__tau_5d_Xe.csv",
  "table": "tbl_3cb99347e778",
  "quantity": "radiative_lifetime",
  "unit": "ns",
  "abscissa": "label",
  "use": "check",
  "parameters": {
    "method": "zero-xenon-pressure intercept of the slow-component rates of collisionally populated 5d[1/2]1 (the zero-argon intercepts at 0.004-3 Torr xenon, Fig. 11); radiation trapped"
  },
  "uncertainty": {
    "column": true,
    "level": "2 sigma"
  }
}

Table III (p. 2922), row ‘This work’, 5d[1/2]1: 111 +- 16 ns (2 sigma), from the intercept of Fig. 11 (decay rates of the collisionally populated level against xenon pressure, themselves zero-argon intercepts); the level is radiation trapped on its 125.0 nm resonance line (p. 2922). A check: NIST’s 1/sum A is 65.6 ns.

bruce_1990/kq_self_Xe#

{
  "id": "kq_self_Xe",
  "material": "Xe",
  "file": "Xe/bruce_1990__kq_self_Xe.csv",
  "table": "tbl_3514df8be433",
  "quantity": "collisional_quenching_rate_coefficient",
  "unit": "cm3/s",
  "scale": 1e-12,
  "abscissa": "label",
  "use": "primary",
  "parameters": {
    "perturber": "self",
    "order": 2,
    "channel": "total",
    "method": "two-photon laser excitation, time-resolved fluorescence, slope of the Stern-Volmer plot"
  },
  "uncertainty": {
    "column": true,
    "level": "2 sigma"
  }
}

Table II (p. 2919), ‘Bimolecular rates (10^-12 cm3/s)’, column ‘This work’: total quenching by xenon of nine levels, 5.9 (6p[1/2]0) to 522 (7p[3/2]2), 2 sigma; 5d[1/2]1 (197 +- 26) from the zero-argon-pressure intercepts at several xenon pressures (footnote c, Fig. 11). The 6p[1/2]0 Stern-Volmer plot was fitted with the termolecular term (kq3_self_Xe).

bruce_1990/kq3_self_Xe#

{
  "id": "kq3_self_Xe",
  "material": "Xe",
  "file": "Xe/bruce_1990__kq3_self_Xe.csv",
  "table": "tbl_3514df8be433",
  "quantity": "collisional_quenching_rate_coefficient",
  "unit": "cm6/s",
  "scale": 1e-31,
  "abscissa": "label",
  "use": "primary",
  "parameters": {
    "perturber": "self",
    "order": 3,
    "channel": "total",
    "method": "two-photon laser excitation, time-resolved fluorescence, slope of the Stern-Volmer plot"
  },
  "uncertainty": {
    "column": true,
    "level": "2 sigma"
  }
}

Table II (p. 2919), ‘Termolecular rates (10^-31 cm6/s)’, ‘This work’: 6p[1/2]0 + 2 Xe, 7.0 +- 0.5 (2 sigma), from a fit with a term in the square of the pressure up to 1000 Torr (p. 2920).

bruce_1990/kq3_bound_Xe#

{
  "id": "kq3_bound_Xe",
  "material": "Xe",
  "file": "Xe/bruce_1990__kq3_bound_Xe.csv",
  "table": "tbl_3514df8be433",
  "quantity": "collisional_quenching_rate_coefficient",
  "unit": "cm6/s",
  "scale": 1e-31,
  "abscissa": "label",
  "use": "check",
  "parameters": {
    "perturber": "self",
    "order": 3,
    "channel": "total",
    "method": "two-photon laser excitation, time-resolved fluorescence, slope of the Stern-Volmer plot"
  },
  "uncertainty": {
    "column": true,
    "level": "bound"
  }
}

Table II (p. 2919), termolecular, 6p[3/2]2: printed ‘<4’, an upper limit from the error bars up to 500 Torr (note added in proof, p. 2925). Held as the interval 0 to 4 x 10^-31 cm6/s: value 2, bound half-width 2 (printed keeps ‘<4’). A check: Moutard et al.’s 6.5 x 10^-30 (text) or 10^-31 (Table II) is outside it.

bruce_1990/kq_Ar_Xe#

{
  "id": "kq_Ar_Xe",
  "material": "Xe",
  "file": "Xe/bruce_1990__kq_Ar_Xe.csv",
  "table": "tbl_b2aa0277aa53",
  "quantity": "collisional_quenching_rate_coefficient",
  "unit": "cm3/s",
  "scale": 1e-12,
  "abscissa": "label",
  "use": "primary",
  "parameters": {
    "perturber": "Ar",
    "order": 2,
    "channel": "total",
    "method": "two-photon laser excitation, time-resolved fluorescence, slope of the Stern-Volmer plot"
  },
  "uncertainty": {
    "column": true,
    "level": "2 sigma"
  }
}

Table IV (p. 2923), ‘Bimolecular rates (10^-12 cm3/s)’, ‘This work’: total quenching by argon of 6p[3/2]2, 6p[5/2]2, 7p[1/2]0, 7p[3/2]2, 7p[5/2]2, 6p’[1/2]0 and 6p’[3/2]2, 40-348, 2 sigma; the xenon rate subtracted at fixed xenon pressure (0.004-5 Torr).

bruce_1990/kq_Ar_coupled_Xe#

{
  "id": "kq_Ar_coupled_Xe",
  "material": "Xe",
  "file": "Xe/bruce_1990__kq_Ar_coupled_Xe.csv",
  "table": "tbl_b2aa0277aa53",
  "quantity": "collisional_quenching_rate_coefficient",
  "unit": "cm3/s",
  "scale": 1e-12,
  "abscissa": "label",
  "use": "check",
  "parameters": {
    "perturber": "Ar",
    "order": 2,
    "channel": "total",
    "method": "slopes of the fast and slow decay rates of the coupled 6p[1/2]0 / 5d[1/2]1 pair against argon density (4 mTorr or 3 Torr xenon)"
  },
  "uncertainty": {
    "column": true,
    "level": "2 sigma"
  }
}

Table IV (p. 2923), ‘This work’, the coupled pair: row 6p[1/2]0, 200 +- 4.0 (footnote b, the fast component of the 828.2 nm decay, Fig. 9a); 5d[1/2]1_slow, 5.9 +- 0.4 (c, the slow component, Fig. 9b); 5d[1/2]1_vuv, 5.5 +- 0.4 (d, the 125 nm fluorescence, Fig. 10). Argon slopes of the two decay eigenvalues of the coupled levels, k12 (1 + chi) and (k10 chi + k20) / (1 + chi) (record notes, script check), not the levels’ removal coefficients, which are k1_Ar and k2_Ar; a check. 2 sigma.