Triplet excimers favoured by charge transfer in electron-donor-acceptor-complexes

The influence of charge transfer complexing both on the triplet-triplet-absorption spectra and of the phosphorescence spectra of the electron donor component has been investigated in giassy solutions in the temperature range T = 96 - 120 degrees K by flash excitation in the CT-absorption band. The TT-absorption spectra, the phosphorescence spectra and the lifetime are changed compared with the non compLexed donor. At higher temperatures and larger donor concentrations the T-excimer formation is favoured by complexing so far as T-state has been excited by charge transfer with complex. singulet excited state vertical bar D(+)A(-)vertical bar(S)* as intermediate.