Energy transfer Forster theory

Non radiative Excitation Energy Transfer (Forster Theory)... 

Here we present a brief review of the physical principles underlying fluorescence energy transfer. The theory was developed primarily by Fdrster and extended by Dexter.Forster did some early experimental studies, and Stryer and Haugland convincingly showed that fluorescence energy transfer could be used as a molecular ruler to measure distances. Emphasis is on developing an intuitive feel for the important relevant parameters. Both a classical and a quantum mechanical approach are given. 

If the conditions for Forster transfer are not applicable, then the theory must be extended. There is recently experimental evidence that coherent energy transfer participates in photosynthesis [74, 75], In this case, the participating molecules are very close together. The excited state of the donor does not completely relax to the Boltzmann distribution before the energy can be shared with the acceptor, and the transfer can no longer be described by a Forster mechanism. We will not discuss this case. There has been active discussion of coherent transfer and very strong interactions in the literature for a longer time [69], and references can be found in some more recent papers [70-72, 76, 77],... 

In the original Forster-Dexter theory [79-81] the superexchange terms in 7), have been ignored, that is, 7, - = //) . We shall present the derivation of their theory in our framework. Consider the energy transfer... 

A detailed theory of energy transfer by the Coulombic mechanism was developed by Forster, so the process is often referred to as Forster resonance energy transfer (FRET). According to the Forster theory, the probability of Coulombic energy transfer falls off inversely with the sixth power of the distance between the donor and the acceptor. For... 

Figure 6.11 The dependence of the efficiency of energy transfer, Er, on the donor-acceptor distance, R, according to the Forster theory...

May V (2009) Beyond the Forster theory of excitation energy transfer importance of higher-order processes in supramolecular antenna systems. Dalton Trans 45 10086-105... 

Th. Forster Quantum mechanical theory of dipole-dipole energy transfer... 

Bifluorophores consisting of two different fluorescent dyes linked by a flexible spacer containing heteroatoms (oxygen, nitrogen or sulfur atoms) can bind cations. This results in a decrease of the distance between the two fluorophores and, consequently, to an increase in efficiency of photoinduced energy transfer between the two moieties (Figure 2.13) provided that the emission spectrum of the donor (D) overlaps the absorption spectrum of the acceptor (A).(36) The transfer efficiency depends on the distance according to Forster s theory ... 

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... 

Scholes GD, Jordanides XJ, Fleming GR (2001) Adapting the Forster theory of energy transfer for modeling dynamics in aggregated molecular assemblies. J Phys Chem B 105 1640... 

Energy transfer experiments permit the measurement of distances because the rate of transfer is proportional to the inverse sixth power of the distance between donor and acceptor. According to the theory of Forster the donor-acceptor distance r is related to the transfer efficiency E by eq 16... 

Fluorescein is an energy acceptor for chromophores such as naphthalene and anthracene and acts as energy donor toward Eosin and Rhodamine, so derivatives have been used for singlet-singlet energy transfer studies. According to Forster s theory [68] the rate constant for energy transfer increases... 

Basile (2) has shown that the nonradiating energy transfer occurring in the system PST-TPB can be described well by the theory of dipole-dipole interaction developed by Forster (7). His calculations show the possibility of a nonradiating energy transfer over distances of 20-25 A. 

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