Spectral, kinetics and redox studies on the transient formed on the pulse radiolysis of aqueous solution of 4-(methylthiophenyl) methanol

Abstract

Pulse radiolysis technique has been employed to investigate the nature and the redox properties of the transient species generated on radiolysis of aqueous solution of (4-methylthiophenyl)methanol (MTPM). Pulse radiolysis in 1,2-dichloroethane, reaction with specific one-electron oxidants (Cl, SO, Tl, Br) and reaction of OH radicals in acidic solution showed absorption bands at 320 and 545nm; these are assigned to solute radical cation with positive charge on the benzene ring. OH-adduct was observed in neutral solution. The oxidation potential for MTPM/MTPM + couple is determined to be 1.55.±.0.04V vs NHE. eaq- reacts with a bimolecular rate constant of 1.5×10 dm mol s and the transient absorption bands (λ=320, 470nm) are assigned to the solute radical anion. E0 value for MTPM/MTPM - couple is determined to be -1.84.±.0.04V vs NHE. The redox properties of the transient species formed on reaction with OH, H, and O have been evaluated.