Spectre d'absorption de l'oxygène

Herman, Luc

doi:10.1051/anphys/193911110548

Cited by 22 publications

(6 citation statements)

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“…The latter are obtained from our recent rotational analysis of the AЈ 3 ⌬ u state (24). The intervals between the peaks are consistent with previous studies (9,10). They are close to the values of the triplet splittings for the AЈ 3 ⌬ u state, which vary from 149.6 to 118.2 cm Ϫ1 for vЈ ϭ 2 to 11, according to the spin-orbit coupling constants A derived by Jenouvrier et al (24).…”

supporting

confidence: 91%

Fourier Transform Spectroscopy of the O2 Herzberg Bands. III. Absorption Cross Sections of the Collision-Induced Bands and of the Herzberg Continuum

Fally

Vandaele

Carleer

et al. 2000

Journal of Molecular Spectroscopy

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Absorption spectra of molecular oxygen were measured in the laboratory under temperature and pressure conditions prevailing in the Earth's atmosphere. Spectra of pure O 2 , O 2 ϩ N 2 , and O 2 ϩ Ar were recorded in the 41 700 to 33 000 cm Ϫ1 region (240 -300 nm) at a maximal optical path difference of 0.45 cm using a Fourier transform spectrometer and a multiple reflection gas cell. The different components of the spectra, namely the discrete bands of the three Herzberg systems, the Herzberg continuum, and the collision-induced diffuse Wulf bands, were separated. The contribution of the Herzberg bands was first subtracted using the line parameters determined previously [A. Jenouvrier, M.-F. Mérienne, B. Coquart, M. Carleer, S. Fally, A. C. Vandaele, C. Hermans, and R. Colin, J. Mol. Spectrosc. 198, 136 -162 (1999)] from high-resolution data. Spectra recorded at various pressures then made it possible to determine by linear regression the intensity of the Wulf bands and the Herzberg continuum. The characteristics of the Wulf bands have been investigated in details: vibrational analysis, pressure effect, foreign gas effect, and a simulated spectrum are reported. The Herzberg continuum cross section is determined below the dissociation limit. A comparison with literature data is given. The new O 2 absorption cross sections and O 2 -O 2 collision-induced absorption cross sections are useful in connection with atmospheric measurements of ozone and other trace gases in the UV spectral region.

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confidence: 91%

Fourier Transform Spectroscopy of the O2 Herzberg Bands. III. Absorption Cross Sections of the Collision-Induced Bands and of the Herzberg Continuum

Fally

Vandaele

Carleer

et al. 2000

Journal of Molecular Spectroscopy

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“…Immediately following this dilution a 2 μm Teflon filter was positioned to prevent aerosols from entering the cavity to minimize losses by Mie scattering. The instrument measured gas-phase glyoxal, NO 2 , and oxygen dimers (O 4 ) from the chamber with a time resolution of 1 min, and a 30 pptv (chamber equivalent concentration) glyoxal detection limit, using WinDOAS software for spectral fitting, and is calibrated from absorption cross-section reference spectra for glyoxal, 43 NO 2 , 44 O 4 , 45 and water. 46 NO x , NO, and NO 2 were monitored by a 42C NO−NO 2 − NO x Analyzer (Thermo Environmental Instruments Inc., Waltham, MA, USA).…”

Section: Methodsmentioning

confidence: 99%

Effective Henry’s Law Partitioning and the Salting Constant of Glyoxal in Aerosols Containing Sulfate

Kampf

Waxman

Slowik

et al. 2013

Environ. Sci. Technol.

128

232

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The reversible partitioning of glyoxal was studied in simulation chamber experiments for the first time by time-resolved measurements of gas-phase and particle-phase concentrations in sulfate-containing aerosols. Two complementary methods for the measurement of glyoxal particle-phase concentrations are compared: (1) an offline method utilizing filter sampling of chamber aerosols followed by HPLC-MS/MS analysis and (2) positive matrix factorization (PMF) analysis of aerosol mass spectrometer (AMS) data. Ammonium sulfate (AS) and internally mixed ammonium sulfate/fulvic acid (AS/FA) seed aerosols both show an exponential increase of effective Henry's law coefficients (KH,eff) with AS concentration (cAS, in mol kg(-1) aerosol liquid water, m = molality) and sulfate ionic strength, I(SO4(2-)) (m). A modified Setschenow plot confirmed that "salting-in" of glyoxal is responsible for the increased partitioning. The salting constant for glyoxal in AS is K(S)CHOCHO = (-0.24 ± 0.02) m(-1), and found to be independent of the presence of FA. The reversible glyoxal uptake can be described by two distinct reservoirs for monomers and higher molecular weight species filling up at characteristic time constants. These time constants are τ1 ≈ 10(2) s and τ2 ≈ 10(4) s at cAS < 12 m, and about 1-2 orders of magnitude slower at higher cAS, suggesting that glyoxal uptake is kinetically limited at high salt concentrations.

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“…The reported values for our peak and integrated s O 4 values compare within 5% of those reported by Hermans 36 as well as S2). 3,[6][7][8]11,12,[15][16][17][18][19][20][21]36,37,[44][45][46][47][48] Prior studies in the atmospheric temperature range of 180-320 K have observed the overall increase of peak s O 4 values with respect to temperature. 6,8,11,12,20,44 Our work is consistent with this finding (Fig.…”

Section: Comparison To Literature Spectramentioning

confidence: 99%

Temperature dependent absorption cross-sections of O2–O2 collision pairs between 340 and 630 nm and at atmospherically relevant pressure

Thalman

Volkamer

2013

Phys. Chem. Chem. Phys.

364

271

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The collisions between two oxygen molecules give rise to O4 absorption in the Earth atmosphere. O4 absorption is relevant to atmospheric transmission and Earth's radiation budget. O4 is further used as a reference gas in Differential Optical Absorption Spectroscopy (DOAS) applications to infer properties of clouds and aerosols. The O4 absorption cross section spectrum of bands centered at 343, 360, 380, 446, 477, 532, 577 and 630 nm is investigated in dry air and oxygen as a function of temperature (203-295 K), and at 820 mbar pressure. We characterize the temperature dependent O4 line shape and provide high precision O4 absorption cross section reference spectra that are suitable for atmospheric O4 measurements. The peak absorption cross-section is found to increase at lower temperatures due to a corresponding narrowing of the spectral band width, while the integrated cross-section remains constant (within <3%, the uncertainty of our measurements). The enthalpy of formation is determined to be ΔH(250) = -0.12 ± 0.12 kJ mol(-1), which is essentially zero, and supports previous assignments of O4 as collision induced absorption (CIA). At 203 K, van der Waals complexes (O(2-dimer)) contribute less than 0.14% to the O4 absorption in air. We conclude that O(2-dimer) is not observable in the Earth atmosphere, and as a consequence the atmospheric O4 distribution is for all practical means and purposes independent of temperature, and can be predicted with an accuracy of better than 10(-3) from knowledge of the oxygen concentration profile.

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Spectre d'absorption de l'oxygène

Cited by 22 publications

References 0 publications

Fourier Transform Spectroscopy of the O2 Herzberg Bands. III. Absorption Cross Sections of the Collision-Induced Bands and of the Herzberg Continuum

Fourier Transform Spectroscopy of the O2 Herzberg Bands. III. Absorption Cross Sections of the Collision-Induced Bands and of the Herzberg Continuum

Effective Henry’s Law Partitioning and the Salting Constant of Glyoxal in Aerosols Containing Sulfate

Temperature dependent absorption cross-sections of O2–O2 collision pairs between 340 and 630 nm and at atmospherically relevant pressure

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