Absorption Cross Sections of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">O</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">O</mml:mi></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>between 2000 and 2800 Å

Shardanand,

doi:10.1103/physrev.186.5

Cited by 49 publications

(14 citation statements)

References 12 publications

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“…The nature of the Wulf bands whose intensity is proportional to the square of the pressure is still controversial: They are attributed either to the 04 dimer, to the (02) 2 collision complex or to collision-induced absorption (CIA) [19][20][21][22].…”

Section: The Wulf Bandsmentioning

confidence: 99%

Absorption cross-sections of atmospheric constituents: NO2, O2, and H2O

Hermans

Vandaele

Carleer

et al. 1999

Environ. Sci. & Pollut. Res.

130

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Absorption spectroscopy, which is widely used for concentration measurements of tropospheric and stratospheric compounds, requires precise values of the absorption cross-sections of the measured species. NO v 02 and its collision-induced absorption spectrum, and H20 absorption cross-sections have been measured at temperature and pressure conditions prevailing in the Earth's atmosphere. Corrections to the generally accepted analysis procedures used to resolve the convolution problem are also proposed.

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Section: The Wulf Bandsmentioning

confidence: 99%

Absorption cross-sections of atmospheric constituents: NO2, O2, and H2O

Hermans

Vandaele

Carleer

et al. 1999

Environ. Sci. & Pollut. Res.

130

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“…Subsequently the O 2 complex was studied at lower temperatures, 4 while some weak absorption phenomena in the 200 -280-nm UV range were also observed. 5 By now the ͑O 2 ͒ 2 absorptions are well characterized, and pressure-dependent cross sections have been derived through the work of Dianov-Klokov, 6 Greenblatt et al, 7 and recently Newnham and Ballard. 8 The collisional complexes relate to an O 2 -O 2 interaction potential, and the broad absorption features observed at room temperature correspond to continuum states at positive energies.…”

Section: Introductionmentioning

confidence: 99%

Visible absorption bands of the (O_2)_2 collision complex at pressures below 760 Torr

Naus

Ubachs

1999

Appl. Opt.

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“…4,10,11 On the basis of measurements of pressure-dependent absorption in pure oxygen, Shardanand estimated the value of the absorption cross section of the O 2 -O 2 pair to be about 1000 times higher than the cross section for free O 2 molecules. 12 Studies of a wide range of X partners in an X -O 2 collision pair 4,10,11 have shown that intermolecular interactions can enhance the O 2 absorption by values up to 10 6 -10 7 . These studies have shown that the ionization potential of the X partner, IP X , is the main factor determining the degree of enhancement in the UV region of the spectrum.…”

Section: Introductionmentioning

confidence: 99%

Cluster-enhanced X–O2 photochemistry (X=CH3I, C3H6, C6H12, and Xe)

Baklanov

Bogdanchikov

Vidma

et al. 2007

The Journal of Chemical Physics

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The effect of a local environment on the photodissociation of molecular oxygen is investigated in the van der Waals complex X -O 2 ͑X=CH 3 I, C 3 H 6 , C 6 H 12 , and Xe͒. A single laser operating at wavelengths around 226 nm is used for both photodissociation of the van der Waals complex and simultaneous detection of the O͑ 3 P J , J =2,1,0͒ atom photoproduct via ͑2+1͒ resonance enhanced multiphoton ionization. The kinetic energy distribution ͑KED͒ and angular anisotropy of the product O atom recoil in this dissociation are measured using the velocity map imaging technique configured for either full ͑"crush"͒ or partial ͑"slice"͒ detection of the three-dimensional O͑ 3 P J ͒ atom product Newton sphere. The measured KED and angular anisotropy reveal a distinct difference in the mechanism of O atom generation from an X -O 2 complex compared to a free O 2 molecule. The authors identify two one-photon excitation pathways, the relative importance of which depends on IPx, the ionization potential of the X partner. One pathway, observed for all complexes independent of IPx, involves a direct transition to the perturbed covalent state X -O 2 ͑AЈ 3 ⌬ u ͒ with excitation localized on the O 2 subunit. The predominantly perpendicular character of this channel relative to the laser polarization detection, together with data on the structure of the complex, allows us to confirm that X partner induced admixing of an X + -O 2 − charge transfer ͑CT͒ state is the perturbing factor resulting in the well-known enhancement of photoabsorption within the Herzberg continuum of molecular oxygen. The second excitation pathway, observed for X -O 2 complexes with X =CH 3 I and C 3 H 6 , involves direct excitation into the 3 ͑X + -O 2 − ͒ CT state of the complex. The subsequent photodissociation of this CT state by the same laser pulse gives rise to the superoxide anion O 2 − , which then photodissociates, providing fast ͑0.69 eV͒ O atoms with a parallel image pattern. Products from the photodissociation of singlet oxygen O 2 ͑b 1 ⌺ g + ͒ are also observed when the CH 3 I-O 2 complex was irradiated. Potential energy surfaces ͑PES͒ for the ground and relevant excited states of the X -O 2 complex have been constructed for CH 3 I-O 2 using the results of CASSCF calculations for the ground and CT states of the complex as well as literature data on PES of the subunits. These model potential energy surfaces allowed us to interpret all of the observed O͑ 3 P J ͒ atom production channels.

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Absorption Cross Sections ofO2andO4between 2000 and 2800 Å

Cited by 49 publications

References 12 publications

Absorption cross-sections of atmospheric constituents: NO2, O2, and H2O

Absorption cross-sections of atmospheric constituents: NO2, O2, and H2O

Visible absorption bands of the (O_2)_2 collision complex at pressures below 760 Torr

Cluster-enhanced X–O2 photochemistry (X=CH3I, C3H6, C6H12, and Xe)

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