Radical rate constants for

Figure 1 kci vs. koH- Second order gas phase rate constants for the reaction of Cl atoms vs. the corresponding OH radicals rate constants for the reactions with a. n-alkanes [11] b. n-alcohols [12] c. n-ethers [12] d. chloroethenes [13] and e. 1-chloroalkanes [14],... 

Studies have been carried out on the methylated complex [H3C-Niin(17)(H20)]2+, which is obtained from the reaction of methyl radicals (generated by pulse radiolysis) with [Ni(17)]2+. The volumes of activation are consistent with the coherent formation of Ni—C and Ni—OH2 bonds, as expected for the generation of a Ni111 complex from a square planar Ni11 precursor.152 The kinetics of reactions of [H3C-Niin(17)(H20)] + involving homolysis, 02 insertion and methyl transfer to Crn(aq) have been determined, and intermediates have been considered relevant as models for biological systems.153 Comparing different alkyl radicals, rate constants for the... 

Atkinson R. 1988. Estimation of gas-phase hydroxyl radical rate constants for organic chemicals. Environ Toxicol Chem 7 435-442. 

Correlation of hydroxyl radical rate constants for aromatics in water vs. Hammett s o constants. (From Haag, W.R. and Yao, C.C.D., Environ. Sci. Technol., 26(5), 1005-1013, 1992. With permission.)... 

Davenport, J. and Mill, T., An SAR for estimating hydroxyl radical rate constants for organic chemicals, Natl. Mtg. Am. Chem. Soc., Div. Environ. Chem., 26(2), 156-161, 1986. 

Anthracene is a polycyclic conjugated structure that cannot be fragmented into smaller units. The oxidants each have preferred points of oxidation on the conjugated rings, but the 9 and 10 positions are favored because of symmetry and stabilization of benzylic radicals. Rate constants for oxidation of anthracene by ROz, 102, and HO have been measured in solution or in vapor kox(R02) is 60 M 1 s 1 in chlorobenzene at 60°C (Mahoney, 1965) ... 

Hydrolysis stable aqueous hydrolysis rate at pH 5, 7, pH 9 measured hydroxy radical rate constant for mecoprop k = 9.0 x 1012 M-1 Ir1 (Armbrust 2000)... 

De AK, Chaudhuri B, Bhattacharjee S, Dutta BK (1999) Estimation of OH Radical Rate Constants for Phenol and Chlorinated Phenols using UV/H2O2 Photo-oxidation, J. Hazard. Mat. B 64 91-104. 

Atkinson, R. (1988). Estimation of Gas-Phase Hydroxyl Radical Rate Constants for Organic Compounds. Environ.Toxicol.Chem., 7,435-442. 

The most important daytime loss process for the biogenics is reaction with OH radicals. Rate constants for the OH reaction with isoprene, a-and /3-pinene are 1.01 X 10-10 cm3 molecule-1 s-1, 5.37 X 10-11 cm3 molecule-1 s-1, and 7.89 X 10 11 cm3 molecule-1 s-1, respectively. Hydroxyl radical reactions with dialkenes and monoterpenes proceed primarily via OH addition across the double bond. Subsequent addition of oxygen to the radical produces a peroxy radical. The reactions of the resulting peroxy radical proceed in a manner similar to those of alkyl peroxy radicals. 

The dominant loss process for HFCs and HCFCs in the atmosphere is reaction with the OH radical. Rate constants for the OH reaction with a wide variety of HFCs and HCFCs are available (Table B.l). A mechanism for the OH reaction of the generalized HFC or HCFC species... 

The equilibrium constant is strongly dependent on the nature of R , which serves an activating function on the C-H bond to be cleaved in the forward reaction and also affects the degree of resonance stabilization in the C-centered radical. Extensive radiation chemical studies on this equilibrium have been conducted, in particular, with alcohols and ethers as reaction partner for the thiyl radical. Rate constants for the forward reaction in these systems typically range from 10 - 10 s l while the back process occurs about four orders of magnitude faster (10 - 10 s ). Equilibrium constants are, accor-... 

Figure 6.18 Correlation of hydroxyl radical rate constants for un-ionized forms of compounds in water versus those in air. Substituted alkanes, open squares alkenes, open circles aromatics, Hlled circles. [Reproduced with permission from W. R. Haag and C. C. D. Yao, Environ. Sci. Technol. 26, 1005 (1992). Copyright 1992, American Chemical Society.]...

Danen, W. C., and R. J. Warner The Remarkable Nucleophlicity of Superoxide Anion Radical. Rate Constants for Reaction of Superoxide Ion with Aliphatic Bromides. Tetrahedron Letts 1977, 989. 

Reactivity of The Carbonate Radical. —Rate constants for the reaction of C63H radicals with several complexes have been measured. Of the labile aquo-ions Co +, Zn +, Ni +, Cu ", and Mn +, only Co (A =2.8x 10 M cm ), Cu + ( 4.5 X 10 M s 0> and Mn (A =1.5x 10 M s ) react at measurable rates the oxidation potential of the metal ion appears to be a governing factor. Two Co -macrocycle complexes, [Coi (2)] and [Co (3)] (see below), whose equatorial co-ordination sites are substitution inert and axial sites have labile HjO, react 200 times faster than Colq, and here the rate is probably substitution limited. ... 

Propagation reactions involve the very fast reaction of oxygen with polsmier alkyl radicals. Rate constants for reactions of most alkyl radicals with oxygen is of the order 10 -10 mol s (23). These reactions lead to the formation of macroalkylperoxyl radicals (Scheme 1, reaction 2), followed by abstraction of a... 

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