Photoinduced charge separation and recombination kinetics in a dimeric iridium(I) complex with covalently bound alkyl-pyridinium acceptors

摘要: In the ideal photochemical energy storage system a photoinduced charge separation must be generated rapidly with minimum loss and maintained by virtue of inefficient electron-hole recombination. These rigorous requirements necessitate thorough understanding diverse parameters that determine barriers to electron-transfer reactions: free changes; donor-acceptor separation, orientation, electron coupling; inner-sphere reorganization energy; solvent dynamics. Clearly, in order elucidate contributions these barriers, model systems prepared which can selectively modified vary one or more parameters. An important requirement for such is covalent coupling donor acceptor into molecule surpass diffusional limits permit study extremely fast intramolecular reactions. They report here results from prototypal synthetic exhibits rate constants vicinity 10/sup 12/ s/sup -1/ at driving forces ca. 1 eV charge-recombination rates slower than 2 x 10/ -1/.