UV Absorption Cross Sections of ClOOCl Are Consistent with Ozone Degradation Models

  title={UV Absorption Cross Sections of ClOOCl Are Consistent with Ozone Degradation Models},
  author={Hsueh-Ying Chen and Chien-Yu Lien and Wei-Yen Lin and Yuan‐Pern Lee and Jim Jr‐Min Lin},
  pages={781 - 784}
Cl in the Sunlight A major assumption in the long-standing mechanistic model for halogen-induced degradation of stratospheric ozone is the steady generation of Cl atoms by photolysis of molecules such as ClOOCl by sunlight. Recently, however, laboratory data raised uncertainties in the ClOOCl absorption cross sections underlying this assumption. Chen et al. (p. 781) undertook precise mass-sensitive cross-section measurements to explore the discrepancy. Molecules were directly quantified before… 
UV photolysis of ClOOCl and the ozone hole.
Newly developed experiments to determine two critical photochemical properties of ClOOCl--its absorption cross section and product branching ratio--including the first reported product branching ratios at 351.8 nm photolysis are focused on.
The UV and visible spectra of chlorine peroxide: Constraining the atmospheric photolysis rate
The photolysis of chlorine peroxide (ClOOCl) is a key chemical step in the depletion of polar stratospheric ozone. As such, precise measurements of the absorption cross sections for ClOOCl are
Photodissociation cross sections of ClOOCl at 248.4 and 266 nm.
This study utilized a mass-resolved detection of ClOOCl to determine its photodissociation cross section, which is the product of the absorption cross section and dissociation quantum yield, and provides a new calibration point for normalizing relative absorption spectra ofClOOCl.
Constraining the chlorine monoxide (ClO)/chlorine peroxide (ClOOCl) equilibrium constant from Aura Microwave Limb Sounder measurements of nighttime ClO
The primary ozone loss process in the cold polar lower stratosphere hinges on chlorine monoxide (ClO) and one of its dimers, chlorine peroxide (ClOOCl). Recently, analyses of atmospheric observations
Constraints for the photolysis rate and the equilibrium constant of ClO‐dimer from airborne and balloon‐borne measurements of chlorine compounds
We analyze measurements of ClO across the terminator taken by the Airborne Submillimeter Radiometer (ASUR) in the activated vortices of the Arctic winters of 1995/1996, 1996/1997, and 1999/2000 to
Can theory quantitatively model stratospheric photolysis? Ab initio estimate of absolute absorption cross sections of ClOOCl.
The general message is that quantitative predictions are difficult even for a relatively small molecule as ClOOCl and the convergence, with respect to the electronic structure method, basis set used, and ground state sampling, needs to be carefully examined.
Does ozone-water complex produce additional OH radicals in the atmosphere?
The results indicate that the OH production through the photolysis of the ozone-water complex is much slower than previously thought.
Photolysis cross-section of ozone dimer.
The synthesis of ozone clusters in a molecular beam by supersonic expansion and indicates that two ozone molecules are only very weakly bound to each other, which agrees with the small MP2 dimerization energy calculated by Slanina and Adamowicz.
Diurnal variation of stratospheric short-lived species
Diurnal variation of stratospheric short-lived species Maryam Khosravi Chalmers University of Technology Department of Earth and Space Sciences Abstract The depletion of ozone in the stratosphere has
Spectra and Photolytic Reactions of Atmospheric Molecules
In this chapter, absorption spectra and cross sections, photolytic pathways and quantum yields are described for important atmospheric molecules that are photolyzed under the actinic flux in the


The UV/Vis absorption spectrum of matrix-isolated dichlorine peroxide, ClOOCl.
The results suggest the existence of a ClOOCl electronic state manifold leading to an absorption band similar to those of the near UV spectrum of Cl(2), which could account for the observed ozone depletion in the spring polar stratosphere.
UV Photolysis of ClOOCl
ClOOCl (ClO dimer) photolysis is believed to dominate the catalytic destruction of polar stratospheric ozone during springtime through the production of atomic chlorine. Decomposition by an alternate
Observation of a Heterogeneous Source of OClO from the Reaction of ClO Radicals on Ice
Experiments presented in this contribution demonstrate a heterogeneous source of several chlorine oxides, in particular OClO and ClClO2, from ClO radicals passed over water−ice surfaces at low
Absorption cross sections of the ClO dimer
K. J. Huder and W. B. DeMore*Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109Received: January 10, 1995; In Final Form: February 3, 1995_NASA-CR-200336The
Kinetics of the ClO Self-Reaction and 210 nm Absorption Cross Section of the ClO Dimer
The kinetics of the dimerization of ClO radicals, ClO + ClO + M → Cl2O2 + M (1a), and the 210 nm absorption cross sections of the ClO dimer have been studied using the technique of flash photolysis
First measurements of ClOOCl in the stratosphere: The coupling of ClOOCl and ClO in the Arctic polar vortex
[1] The first measurements of ClOOCl in the stratosphere have been acquired from a NASA ER-2 aircraft, deployed from Kiruna, Sweden (68°N, 21°E), during the joint SOLVE/THESEO-2000 mission of the
Thermal decomposition of ClOOCl.
The decomposition rate constants of ClOOCl were directly measured for the first time, and they are higher, depending on temperature and pressure, by factors between 1.5 and 4.2 as compared to experimental data on k-1 by Nickolaisen et al.
The stability and photochemistry of dimers of the ClO radical and implications for Antarctic ozone depletion
Measurements of the ultraviolet spectrum of the Cl2O2 molecule formed at temperatures in the range 203–300 K by recombination of ClO radicals are reported. The equilibrium constant for the reaction
Bond strength of chlorine peroxide.
An approximation for the equilibrium constant in the stratospheric temperature regime between 190 and 230 K of the form K(eq) = 1.92 x 10(-27) cm3 molecules(-1) x exp(8430 K/T) is provided, lower than current reference data and agrees well with high altitude aircraft measurements within their scattering range.
Large losses of total ozone in Antarctica reveal seasonal ClOx/NOx interaction
Recent attempts1,2 to consolidate assessments of the effect of human activities on stratospheric ozone (O3) using one-dimensional models for 30° N have suggested that perturbations of total O3 will