Spin conversion charge separation yield

Here we will confine ourselves mainly to the incoherent (rate) description of spin conversion, which provides the simplest way to account for spin-forbidden recombination of RIPs in complex photochemical reactions. Since ks from Eq. (3.557) depends on H through co-(H), the charge separation yield is also affected by the magnetic field. Therefore, the ratio... 

Even more straightforward evidence in favor of recombination to the triplet state was obtained by heavy-atom substitution into the fluorescence quencher, which also enhances the rate of spin conversion. By measuring the transient absorption of both ion radicals and the triplet products of their recombination, it was demonstrated that the quantum yield of triplets increases when the charge separation yield 9(0) decreases as a result of heavy-atom substitution [225]. As was shown in Figure 3.76, triplet state is faster than to the singlet state, while the quantum yield of triplets produced from the singlet precursor only increases with ks. Hence these data also indicate that the triplet channel of recombination is the most efficient. 

However, the theory of exciplex dissociation cannot be made spinless like that for photoacids (Section V.D). The dissociation products are radical ions and the spin conversion in RIPs essentially affects

other quantities listed in Eq. (3.589). To illustrate this phenomenon, let us concentrate on the fluorescence yield, which is affected through %E(ks) and the charge separation quantum yield cp(cr). We will consider the general solution obtained for these two quantities in Ref. 31 only in the simplest case of highly polar solvents for which the Green functions are well known. 

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