Electron-transfer and excited-state properties of radiolytically generatedtransients of acridine(1,8)dione dyes in an organic matrix

Pulse radiolysis technique has been employed to generate and investigate el ection and energy transfer reactions involving acridine(1,8)dione dyes in h ydrocarbons. The transient absorption spectra obtained on pulse radiolysis of N-2-saturated solution in 1,2-dichloroethane are assigned to solute radi cal cation. The radical cations undergo charge transfer reaction with tetra methyl-p-phenylenediamine and triethyl amine. The transient absorption spec tra in Nz-saturated solution in benzene are assigned to triplet-triplet abs orption. It was observed that biphenyl, p-terphenyl and benzophenone triple ts undergo energy transfer to methyl and phenyl substituted acridine(1,8)di one dyes generating the triplets of the acceptor. With H substituted acridi ne(1,8)dione dye, benzophenone and chloranil triplets favor electron-transf er followed by Hf transfer reaction forming benzophenone ketyl and chlorani l semiquinone radicals respectively. (C) 2001 Published by Elsevier Science B.V.