TIME-RESOLVED EPR STUDY OF C-3(60) IN SOLID MATRICES

Using time-resolved cw EPR and pulsed EPR techniques, a study was made of the characteristics of the photoexcited triplet state of C-60 adso rbed in silica gel pores and embedded in a polymethylmethacrylate matr ix. It was found that the time-resolved spectra from C-3(60) in these matrices at room temperature retain the absorption/emission features o f spectra from C-3(60) in frozen solution (less than or equal to 120 K ). Apparently, the combination of molecular rotation and pseudo rotati on (resulting from interconversion between Jahn-Teller states) is not fast enough to lead to complete averaging of the dipole-dipole interac tion between the unpaired electrons. The study explored the effect of introduction of solvent molecules in the silica gel pores on the C-3(6 0) spectrum and quenching of the triplet by electron donors.