Photochemistry of 9,10-anthraquinone-2-sulfonate in solution. Part II. Effects of inorganic anions; quenching vs. radical formation at moderate and high anion concentrations

Technical Report · Fri Dec 30 04:00:00 EST 1983

OSTI ID:5473816

Loeff, I; Treinin, A; Linschitz, H

The chemical aspects of the interactions between excited 9, 10-anthraquinone-2-sulfonate (AQS) and various inorganic anions are examined. The anions which quench triplet AQS can be divided into two groups: Cl/sup -/, Br/sup -/, I/sup -/ and NCS/sup -/ (Group I) photoreduce the quinone to AQS/sup -/ only at concentrations higher than that required for complete triplet quenching. The effect increases with concentration and passes through a maximum with highest quantum yields of radical formation reaching approx. 1 for Cl/sup -/ and NCS/sup -/; NO/sub 2//sup -/, SO/sub 3//sup 2 -/ and N/sub 3//sup -/ (Group II) reduce AQS in parallel to triplet quenching. The nature of the high-concentration effect shown by Group I is analyzed. Some results obtained with mixtures of anions support the conclusion that triplet AQS is also responsible for this effect and it is suggested that triple exciplexes of the type /sup 3/(AQS/sup -/.X/sub 2//sup -/) are involved. With this view and the recently proposed intra-radical-spin-orbit-coupling (IRSOC) model, a quantitative interpretation of the results is presented.

• Research Organization: Brandeis Univ., Waltham, MA (USA). Dept. of Chemistry
• DOE Contract Number: AC02-76ER03117
• OSTI ID: 5473816
• Report Number(s): DOE/ER/03117-27; COO-3117-27; ON: DE84005151
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
ANIONS
ANTHRAQUINONES
AROMATICS
CHARGED PARTICLES
CHEMISTRY
DISPERSIONS
IONS
MIXTURES
MULTIPLETS
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PHOTOCHEMISTRY
QUINONES
RADICALS
SOLUTIONS
SULFONATES
TRIPLETS