Hydrogen-transfer and charge transfer in photochemical and high energy radiation induced reactions: effects of thiols. Final report, February 1, 1960-January 31, 1979

Technical Report · Sat Mar 01 00:00:00 EST 1980

DOI:https://doi.org/10.2172/5295452· OSTI ID:5295452

Cohen, S. G.

Absorption of ultraviolet or visible light, or high energy radiation, may lead to highly reactive free radicals. Thiols affect the reactions of these radicals in the following ways: (1) transfer of hydrogen from sulfur of the thiol to a substrate radical, converting the radical to a stable molecule, and the thiol to a reactive thiyl radical; and (2) transfer of hydrogen from a substrate radical or molecule to thiyl, regenerating thiol. The thiol is thus used repeatedly and a single molecule may affect the consequences of many quanta. Three effects may ensue, depending upon the system irradiated: (1) the substrate radicals may be converted by thiol-thiyl to the original molecules, and protection against radiation damage is afforded. (2) The radicals may be converted to molecules not identical with the starting materials, and in both cases damage caused by radical combination processes is prevented. (3) Product yields may be increased where the initial radicals might otherwise regenerate starting materials. It was shown that rates of reaction of excited species can be correlated with triplet energies and reduction potentials, and with ionization potentials, that amines are very reactive toward excited carbonyl compounds of all types, and that yields of products from these reactions can be increased by thiols, leading to increased efficiency in utilization of light.

• Research Organization: Brandeis Univ., Waltham, MA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: EY-76-S-02-3118
• OSTI ID: 5295452
• Report Number(s): DOE/ER/03118-13; TRN: 80-010596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
ORGANIC COMPOUNDS
PHOTOCHEMICAL REACTIONS
RADICALS
THIOLS
AMINES
AROMATICS
CHARGE EXCHANGE
HYDROGEN TRANSFER
ORGANIC OXYGEN COMPOUNDS
RADIOLYSIS
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
DECOMPOSITION
ORGANIC SULFUR COMPOUNDS
RADIATION CHEMISTRY
RADIATION EFFECTS
400500* - Photochemistry
400600 - Radiation Chemistry