Charge recombination reorganization energies

Recently, photochemical and photoelectrochemical properties of fullerene (Cto) have been widely studied [60]. Photoinduced electron-transfer reactions of donor-Qo linked molecules have also been reported [61-63]. In a series of donor-Cfio linked systems, some of the compounds show novel properties, which accelerate photoinduced charge separation and decelerate charge recombination [61, 62]. These properties have been explained by the remarkably small reorganization energy in their electron-transfer reactions. The porphyrin-Qo linked compounds, where the porphyrin moieties act as both donors and sensitizers, have been extensively studied [61, 62]. 

Phenothiazine (PTZ) and ferrocene (Fc), both of which have a small reorganization energy associated to the electron transfer, are the first comediators that have been considered. Each has a potential that falls between 0.22 and 0.75 V versus SCE, respectively, the potential of the Co(DTB)33+/2+ and of the dye [Ru(H2DCB)-(dnbpy)(NCS)2]+/0. Because of the facile electron transfer, the photooxidized dye would be predominantly reduced by the comediator. Its oxidized form (PTZ+ and Fc +) can then be rapidly intercepted by Co(II), preventing the direct charge recombination between the oxidized comediator and the electrons in the 2. Nanosecond... 

Both the inequality of the charge separation (CS) and charge recombination (CR) reorganization energies (A,i Xz, Figure 8) and the deviation from... 

In contrast, charge recombination processes from CS states produced by photoinitiation normally take place within the inverted region. Thus, the small reorganization energy of Ceo will slow down CR processes, relative to other acceptors having higher 2, values. 

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