The photochemistry of 9,10-anthraquinone-2-sulfonate in solution. 2. Effects of inorganic anions: quenching vs. radical formation at moderate and high anion concentrations

Abstract

The chemical aspects of the interactions between excited 9,lO-anthraquinone-2-sulfonate (AQS) and various inorganic anions are examined. The anions which quench triplet AQS can be divided into two groups: Cl-, Br-, I-and NCS-(group I) photoreduce AQS to AQS-radical anion 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 N 1 for C1-and NCS-; on the other hand, NOz-, SO3*-, and N; (group 11) give 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 3(AQS-.X;) are involved. With this view and the recently proposed intraradical spin-orbit-coupling (IRSOC) model, a quantitative interpretation of the results is presented.

Interactions between 9,10-anthraquinone and aromatic amines in homogeneous and micellar media: A laser flash photolysis and magnetic field effect study

“…Both the spectra of AQ in presence of DMA and DMDPM also exhibit peaks around 390 nm and 540 nm. It has been reported that 9,10-anthraquinone-2-sulfonate radical anion has l max at 385 nm and 510 nm [20,21]. So probably the peaks at 390 nm and 540 nm are due to the formation of AQ dÀ .…”

Anthraquinone‐Sensitized Photooxidation of 5‐Methylcytosine in DNA Leading to Piperidine‐Induced Efficient Strand Cleavage

“…[19] It is therefore most likely that the triplet excited-state chromophore 3 (Figure 2 b). By reference to the previous study, [21] this transient species is assigned to an AQS radical anion (AQSC À ). The AQSC À species formation gave a pseudo-first-order rate constant of 1.…”

Photomutagenicity of 16 polycyclic aromatic hydrocarbons from the US EPA priority pollutant list

“…Light-induced DNA cleavage or DNA adduct formation is greatly affected by co-existing chemicals [18,20,38,39]. Likewise, the photodegradation rate and the percent of each photoproduct are greatly affected by various factors [40][41][42][43]. Therefore, detailed mechanistic understanding on the photochemistry of PAHs is needed in order to determine the relationship between photomutagenicity and structure of the PAHs.…”