PICOSECOND DYNAMICS OF PHOTOINDUCED ELECTRON-TRANSFER PROCESSES IN POLY(N-VINYLCARBAZOLE) SOLID FILM DOPED WITH ELECTRON-ACCEPTORS AS REVEALED BY TRANSIENT ABSORPTION-SPECTROSCOPY AND DICHROISM MEASUREMENTS

Combining the measurements of the picosecond transient absorption spectra and the transient dichroism sensitive to the charge shift reaction processes, photoinduced charge separation (CS), recombination (CR) and hole transfer (HT) processes in poly (N-vinylcarbazole) solid films doped with electron acceptors were investigated. It was observed that the HT process was in competition with the CR in the initial charge-separated state produced via the excitation of the ground state CT complex. The time constant for the HT from the cation state of carbazole moiety (Cz) to neighboring Czs was obtained to be almost-equal-to 2 ns. Primary processes in these photoinduced electron transfer phenomena were discussed by comparing the present results with those in solutions.