Porphyrin ion pair

Fermin, D.J., H.D. Duong, Z.F. Ding, P.F. Brevet, and H.H. Girault (1999). Photo-induced electron-transfer at Uquid/hquid interfaces— part HI— Photoelectrochemical responses involving porphyrin ion-pairs. J. Am. Chem. Soc. 121,10203-10210. 

In part VI, the dynamics of photoinduced heterogeneous electron transfer between a series of ferrocene derivatives and porphyrin ion pairs introduced in part IV was studied. In particular, the use of various ferrocene derivatives with... 

In 2003, the initial stages of the heterogeneous photoreduction of quinone species by self-assembled porphyrin ion pairs at the H20-1,2-DCE interface were studied by ultrafast time-resolved spectroscopy and dynamic photo-electrochemical measurements. Photoexcitation of the water-soluble ion pair formed by ZnTPPS and ZnTMPyP + leads to a charge-separated state of the form ZnTPPS -ZnTMPyP + within 40 ps that can inject electrons to acceptors in the organic phase in the microsecond time scale, resulting in photocurrent responses [228]. 

Eugster, N., D. J. Fermin, and H. H. Girault, Photoinduced electron transfer at liquid I liquid interfaces Dynamics of the heterogeneous photoreduction of quinones by self-assembled porphyrin ion pairs, J Am Chem Soc, Vol. 125, (2003) p. 4862. 

Samsonova and Nikiforov, 1984), and porphyrin and phthalocyanine metal complexes (Becker et al., 1985a, 1986b Becker and Grossmann, 1990) were tested. That a series of relatively simple anions such as the oxalate monoanion, tetraphenyl bor-anate (Ph4B ), bromide, chloride, and even tetrafluoroborate can act as donors is, at least for the last mentioned anion, surprising, but Becker et al. (1985 b) were able to trap aryl radicals and in some cases also donor radicals (Cl, COO ) by spin trapping with nitrosodurene and phenyl-tert-butylnitrone. The photochemical effect is postulated to be due to ion pairs ArNJ X-. 

In contrast to the case of ZnCh-Ceo, no transient formation of Ceo" was detected at 1000 nm for any other dyad in Scheme 4b [65]. In each case, only the triplet-triplet absorption due to the chlorin or porphyrin moiety was observed due to the higher energy of the radical ion pair as compared to the triplet excited state as is expected from the redox potentials. Thus, the energy level of the radical ion pair in reference to the triplet energy of a component is an important factor in determining the lifetime of the radical ion pair. 

A number of authors have called the formation of SAT complex into question and instead suggested either (c) direct coordination between the metal ion and two pyrrolinine nitrogen atoms of the porphyrin to give H2PM2+ or (d) ion pair formation between the porphyrin dication and solvated anion formed in solvents incapable of supporting separate charged species was proposed (93). 

Investigations of the photoinduced electron transfer between fullerenes and porphyrines show that electron transfer occur from the porphyrin to 3C o/3C o-Additionally, due to the absorption of the porphyrines at the excitation wavelength, electron transfer from triplet-excited porphyrine to fullerene may occur. Both pathways lead to the radical ion pair, the ratio depends on the ratio of con-... 

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