Donor-Acceptor energy transfer

Several modified phthalocyanine compounds have been found to effectively stabilise rubber/ Other unusual stabilisers include piperylene-methyl-styrene in poly(ethylene), dioxynaphthylpropane in polyfethylene), ketones and anilines for poly(3-butylthiophene), thioglycerol for wood pulp and dibutylphthalate for PMMA/ N-Arylphthalimides are self stabilising due to their donor-acceptor energy transfer properties/ ... 

Ro critical radius for donor-acceptor energy transfer... 

Cook, R. M. Lyttle, M. Dick, D. Synthesis and methods for dark quencher probes for donor-acceptor energy transfer. PCT Int. Appl. WO 2001086001, 2001 Chem. Abstr. 2001,135, 368945. 

This step is similar to that of the donor acceptor energy transfer shown in equation (9) (D - - A D -I- A ). It is a nomadiative deactivation of the ligand, which yields to the excitation of the lanthanide ion. The ligand is thus the excited donor D and the lanthaiude ion the acceptor A. 

For other distributions and/or dimensionalities the donor decay becomes more complex with assuming values equal to 1/6 and 1/3 for one and two dimensional systems, respectively [85, 86]. In many cases, such as photon-harvesting polymer systems, where a distribution of relaxation times is expected, due to intrachain donor-acceptor energy transfer steps, either the distributions and/or the dimensionality are difficult to define a priori. Thus the use of a stretched exponential (Eq. 15.61, where 0 < / < 1 is an empirical parameter) has been proposed. 

We then introduce a few examples for the use of SPFS, first in surface hybridization studies and then for antigen-antibody interaction assays. We will give, in particular, examples for different versions of fluorescence spectroscopy making use of, e.g., donor-acceptor energy transfer phenomena between correspondingly labeled binding partners. 

Figure 6.9. Ideal donor-acceptor energy level arrangement for triplet-triplet energy A transfer.

Fig. 8 Schematic illustration of donor/acceptor energies relevant for charge-transfer in organic solar cells. Straight lines represent ground state binding energies, while wavy lines represent excited state binding energies...

Figure 6.14 Three donor-acceptor energy level schemes for quenching by energy transfer. 1. Benzophenone (D)+naphthalene (A) ...

Inokuti and Hirayama [185] derived these expressions from a rather less formal approach by considering the ensemble-averaged rate of decay of each donor by energy transfer to each acceptor. A more detailed and general analysis has been given by Allinger and Blumen [186], Finally... 

Dimole absorption and emission, 247 Dioxetane formation, 253 Donor-acceptor energy levels, 201 property, energies of, 289 Dipole-dipole resonance energy transfer, 192, 193... 

Fig. 1 A schematic view of the donor-acceptor photophysics. D/A and D /A correspond to the ground and excited donor/acceptor, respectively. It is assumed that only the donor is photoexcited at the rate of k X. Icet is the donor-to-acceptor energy transfer rate constant, and ko/kA are the free donor/acceptor fluorescence rate constants.

The role of mediator molecules in donor-acceptor electron transfer processes is an item of considerable recent interest [73 — 81]. A lot of research has been done on intermediate acceptors in the electron transfer in photosynthesis and theoretical studies bases on the superexchange interaction have been carried out [76 — 82]. In Refs. [83,84], electron transfer in the presence of ordered mediator molecules with arbitrary energy levels in one-dimensional case [83] as well as electron transfer in the presence of one resonant mediator [84] were considered. 

Figure 11. Schematic energy diagram for extrinsic carrier generation in a donor-acceptor charge transfer system. (Reprinted with permission from Ref. [29n].)...

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