An ENDOR study has been made of the photoexcited triplets of some cyano-substituted zinc tetraphenylporphyrins randomly oriented in a rigid matrix. The results demonstrate that the ENDOR method can be applied in studies of short-lived triplets (triplet lifetime 1 ms) in amorphous solids. The application is possible because of the fact that the ESR signal intensity is strongly enhanced by electron spin alignment. As a consequence of the spin alignment, ENDOR spectra can appear in absorption or emission depending on the field setting employed. Hyperfine data derived from the spectra reflect the effect of CN substitution on the electron spin distribution.
展开▼
