Reduction Potentials of One-Electron Couples Involving Free Radicals in Aqueous Solution

Journal Article · Sun Oct 01 00:00:00 EDT 1989 · Journal of Physical and Chemical Reference Data; (USA)

DOI:https://doi.org/10.1063/1.555843· OSTI ID:7020733

Wardman, P ^[1]

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1. Gray Laboratory of the Cancer Research Campaign, Mount Vernon Hospital, Northwood Middlesex HA6 2JR, United Kingdom (GB)

Reduction of an electron acceptor (oxidant), A, or oxidation of an electron donor (reductant), A{sup 2{minus}}, is often achieved stepwise {ital via} one-electron processes involving the couples A/A{center dot}{sup {minus}} or A{center dot}{sup {minus}}/A{sup 2{minus}} (or corresponding prototropic conjugates such as A/AH{center dot} or AH{center dot}/AH{sub 2}). The intermediate A{center dot}{sup {minus}}(AH{center dot}) is a free radical. The reduction potentials of such one-electron couples are of value in predicting the direction or feasibility, and in some instances the rate constants, of many free-radical reactions. Electrochemical methods have limited applicability in measuring these properties of frequently unstable species, but fast, kinetic spectrophotometry (especially pulse radiolysis) has widespread application in this area. Tables of {ital ca}. 1200 values of reduction potentials of {ital ca}. 700 one-electron couples in aqueous solution are presented. The majority of organic oxidants listed are quinones, nitroaryl and bipyridinium compounds. Reductants include phenols, aromatic amines, indoles and pyrimidines, thiols and phenothiazines. Inorganic couples largely involve compounds of oxygen, sulfur, nitrogen and the halogens. Proteins, enzymes and metals and their complexes are excluded.

• OSTI ID: 7020733
• Journal Information: Journal of Physical and Chemical Reference Data; (USA), Journal Name: Journal of Physical and Chemical Reference Data; (USA) Vol. 18:4; ISSN 0047-2689; ISSN JPCRB
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600* -- Radiation Chemistry
AMINES
AMMONIUM COMPOUNDS
AQUEOUS SOLUTIONS
AROMATICS
AZAARENES
AZINES
AZOLES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHEMISTRY
DATA
DATA COMPILATION
DISPERSIONS
DOCUMENT TYPES
ELECTRON TRANSFER
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
INDOLES
INFORMATION
KINETICS
MIXTURES
NITRO COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXIDATION
PHENOLS
PHENOTHIAZINES
PYRIDINES
PYRIDINIUM COMPOUNDS
PYRIMIDINES
PYRROLES
QUATERNARY COMPOUNDS
QUINONES
RADIATION CHEMISTRY
RADICALS
REACTION KINETICS
REDOX POTENTIAL
REDUCTION
REVIEWS
SOLUTIONS
THIOLS