Electronic singlet energy transfer

The theory of resonance transfer of electronic excitation energy between donor and acceptor molecules of suitable spectroscopic properties was first presented by Forster.(7) According to this theory, the rate constant for singlet energy transfer from an excited donor to a chromophore acceptor which may or may not be fluorescent is proportional to r 6, where r is the distance... 

These two molecules were the antecedents of a variety of oligomeric porphyrin and chlorophyll derivatives which were constructed as mimics of the reaction center special pair. Many of these systems exhibit interesting optical properties which allow modelling of the electronic interactions within the special pair and/or the antenna function of chlorophyll, which involves singlet-singlet energy transfer... 

The authors state that it is possible to metallate the outer porphyrin moiety of 14 while leaving the inner porphyrin in the free base form. If this can be done with a metal such as zinc, the monometallated derivative should favor singlet energy transfer to the central porphyrin, which can serve as an electron donor to... 

Finally, it should be noted that singlet-state lifetimes in [Re(L)(CO)3(bpy)], are long enough to allow for ultrafast electron or energy transfer in supramolecular assemblies, at surfaces or molecule/nanoparticle interfaces, see Sect. 7.3. Indeed, a hot electron injection has been seen with Ti02 nanoparticles [42] or in Re-labeled redox proteins [43],... 

C S, So-H heat (10 M0 s) ISC inter system crossing T, ->So -t heat (10" -10 s) ISC S, T, -H heat (10-"-10" s). P, Reaction product from the singlet state (intramolecular) P2 (intermolecular) reaction product from the triplet state. The reactions from Sj and T] may also include electron or energy transfer reactions. The arrows in the boxes represent the spin orientation of the electrons in the participating MOs. 

Singlet-singlet energy transfer Transfer of excitation from an electronically excited donor in a singlet state to produce an electronically excited acceptor in a singlet state. 

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