Halogen oxide radicals, kinetics

Bedjanian Y, Poulet G (2003) Kinetics of Halogen Oxide Radicals in the Stratosphere. 

Laboratory kinetic measurements have shown that the reactions of DMS with halogen oxide radicals, specially IO, and probably to a much lesser extent CIO and BrO, are potentially important in the DMS oxidation in the marine atmosphere. Tne reaction of DMS with IO could explain the lower values of the DMS lifetime obtained from different field measurements. These values range from fractions of a hour to approximately 40 hours. The present paper successively reports on these field measurements, the laboratory kinetic data obtained for the reaction of DMS with IO,... 

Kinetic Studies of the Reactions of Halogen Oxide Radicals IQ. BrO and CIO... 

Bedjanian, Y., Poulet, G. Kinetics of halogen oxide radicals in the stratosphere. Chem. Rev. 103, 4639 655 (2003)... 

As discussed in Chapters 7, 8, and 9, there are a number of free radical species whose reactions in the aqueous phase drive the chemistry of clouds and fogs. These include OH, HOz, NO-, halogen radicals such as Cl2, sulfur oxide radicals, and R02. Generation of these radicals in the liquid phase for use in kinetic... 

The atmospheric oxidation of dimethyl sulfide (DMS) and DMSO has been reviewed. Kinetics of oxidation of DMS and DMSO with OH and NO3 radicals and with halogen and halogen oxides have been described and the mechanistic aspects have been discussed.244 A review of recent studies of the mechanism and kinetics of the gas-phase oxidation of dimethyl ether has mentioned the pressure dependence of the... 

The reader is referred to Pryde (86) for a more thorough discussion on the kinetics of autoxidation of phospholipids their forming metal ion, iodine, and other complexes halogen addition and their behavior during hydration, hydrogenation (with heterogeneous and homogeneous catalysts), hydrolysis and alcoholysis, hydroxylation, oxidation, radical, and other reactions. 

Clearly, this discovery has an important bearing on the kinetics of the decompositions of chlorine oxides and of the halogen-sensitized decompositions of oxides, e.g. 03 and N20. Johnston et alf21 have recently shown that an additional, pressure-dependent reaction occurs between two CIO radicals, viz... 

There are a large number of chain reactions that are significant in industrial processes or play an important role for the environment. Classes of chain reactions that are relevant industrially include hydrogen/halogen reactions and pyrolysis of hydrocarbons, which are both discussed below, and free-radical polymerization discussed in many textbooks on kinetics. As an example of a chain reaction of significant environmental consequence, we will discuss formation of nitric oxide from fixation of atmospheric nitrogen. 

Chromium(n). The applications of chromium(n) salts in preparative organic chemistry have been reviewed.69 The kinetics of oxidation of Cr11 to Crm by halogen radical anions, a particularly simple one-electron oxidation scheme, have been determined.70 Hydrated electrons are formed71 during the photochemical oxidation of aqueous chromium(n). 

The CN radical is a pseudo-halogen, i.e. its chemistry resembles that of a halogen atom, X it forms C2N2, HCN and [CN] , analogues of X2, HX and X . Although C2N2 and HCN are thermodynamically unstable with respect to decomposition into their elements, hydrolysis by H2O, and oxidation by O2, they and [CN] are kinetically stable enough for them to be well-established and much studied species. 

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