Identification and Characterization of Aqueous Ferryl(IV) Ion
The reaction between ferrous ions and ozone in acidified aqueous solution generates a short-lived species (t{sub 1/2} as 7 sec), which was identified as high-spin pentaaquairon(IV) oxo dication (ferryl) by UV-Vis, Mossbauer, XAS spectroscopies, DFT calculations, {sup 18}O isotopic labeling, and conductometric kinetic studies. Kinetic and {sup 18}O isotopic labeling studies were used to determine the rate constant for the oxo group exchange between ferryl and solvent water, k{sub ex} = 1400 s{sup -1}. Oxidation of alcohols, aldehydes, and ethers by ferryl occurs by simultaneous hydrogen atom and hydride transfer mechanisms. Ferryl was also found to be an efficient oxygen atom transfer reagent in the reactions with sulfoxides, a water soluble phosphine, and a thiolato-complex of cobalt(III). A quantitative and fast reaction between ferryl and DMSO (k{sub DMSO} = 1.3 x 10{sup 5} M{sup -1} s{sup -1}) produces methyl sulfone. This and some other findings unambiguously rule out ferryl as a Fenton intermediate.
- Research Organization:
- Ames Lab., Ames, IA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- DE-AC02-07CH11358
- OSTI ID:
- 965398
- Report Number(s):
- IS-J 7516; TRN: US200919%%697
- Journal Information:
- ACS Symposium Series, Vol. 985
- Country of Publication:
- United States
- Language:
- English
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